Iodinated anion exchange resin and process for preparing same

ABSTRACT

The present invention relates to iodinated resins. It relates in particular to a process for preparing a polyiodide-resin wherein an anion exchange resin is contacted with a material capable of donating a member absorbable by the resin so as to convert the resin to the polyiodide-resin. The absorbable member is selected from the group consisting of I 2  and polyiodide ion having a valence of −1. In the process, conversion of the anion exchange resin to the polyiodide-resin is effected at elevated temperature and/or elevated pressure, the elevated temperature being about 100° C. or higher, the elevated pressure being greater than atmospheric pressure. The present invention also relates to a substance comprising an iodine (impregnated) resin as produced by the above process.

CLAIM OF PRIORITY

This application is a continuation-in-part of U.S. patent applicationSer. No. 09/465,968, filed on Dec. 14, 1999 now abandoned, which is adivisional of U.S. patent application Ser. No. 08/803,869, filed on Feb.24, 1997, now U.S. Pat. No. 6,045,820, which is a divisional of U.S.patent application Ser. No. 08/256,425, filed Jul. 12, 1994, now U.S.Pat. No. 5,639,452 filed as PCT/CA93/00378 on Sep. 15, 1993, which is acontinuation-in-part of U.S. patent application Ser. No. 07/957,307filed Sep. 16, 1992, now abandoned, and a continuation-in-part of U.S.patent application Ser. No. 08/047,535 filed on Apr. 19, 1993, nowabandoned. This application incorporates by reference in its entiretythe contents of co-pending U.S. patent application Ser. No. 09/465,968,filed on Dec. 14, 1999.

FIELD OF THE INVENTION

The present invention relates to an iodinated anion exchange resin andto a process for the preparation thereof. The iodinated anion exchangeresin may be used to sterilize a fluid such as, for example, water, air,as well as fluid exudate secreted at body lesions or traumas such as atcuts, burns, etc.; thus, the iodinated resin may be used to devitalizemicroorganisms (e.g. bacteria, viruses, etc.) which may be present inthe fluid (e.g. water, air, pus and the like). The treatment of fluid,such as water or air, with iodinated anion exchange resin of the presentinvention may leave behind non-detectable (or acceptable) residualdiatomic iodine in the fluid (e.g. water or air). The present inventionin particular relates to a demand type broad spectrum resin-polyiodide(e.g. water, air, wound) disinfectant. The iodinated anion exchangeresin may also be used to deactivate or substantially reduce theeffectiveness of toxic chemical agents.

BACKGROUND OF THE INVENTION

Diatomic halogen (such as I₂, Cl₂, Br₂, etc.) has traditionally beenused to disinfect water. Diatomic chlorine, for example, is a widelyexploited disinfectant for controlling or eliminating micro-organismswhich may be present in water. A disadvantage of a sterilization regimewhich exploits diatomic halogen is that the regime may leave behindunacceptable (residual) levels of halogen in the water oncesterilization is complete.

An iodine/resin product has, however, been proposed for use as a demanddisinfectant, namely a disinfectant wherein iodine is released almostentirely on a demand-action basis. U.S. Pat. Nos. 3,817,860, 3,923,665,4,238,477 and 4,420,590 teach such a demand disinfectant wherein iodineis the active disinfectant agent; the entire contents of each of thesepatents is incorporated herein by reference. In accordance with theteachings of these patents the resin product may be used without fear ofintroducing unacceptable concentrations of diatomic iodine into thewater to be sterilized.

U.S. Pat. Nos. 3,817,860 and 3,923,665 teach an iodine/resin demanddisinfectant which is the reaction product obtained by contacting astrong base anion exchange resin with a suitable source of triiodideions. The reaction product is taught as being very stable in the sensethat the amount of iodine (e.g. I₂) released into water from thereaction product is sufficiently low that the water disinfected therebyis immediately ready for use, ie. as drinking water.

In accordance with the teachings of U.S. Pat. Nos. 3,817,860 and3,923,665 the procedure for preparing the iodine/resin comprises forminga triiodide ion (solution or sludge) by dissolving diatomic iodine in awater solution of a suitable alkali metal halide (e.g. KI, NaI, . . . ).The triiodide solution is in particular taught as being made with aminimal (i.e. minor) water content just sufficient to avoid causing theI₂ to crystallize out; see example 1 of U.S. Pat. No. 3,923,665. Theresulting (solution) containing the triiodide ion is then contacted withthe starting resin (under ambient conditions with respect to temperature(i.e. 25 to 30° C.) and pressure), the triiodide ions exchanging withthe anion of the resin (e.g. exchange with chlorine, sulfate, etc.,).The starting resin is taught as being a porous granular strong baseanion exchange resin having strongly basic groups in a salt form whereinthe anion thereof is exchangeable with triiodide ions. In accordancewith the teachings of the above prior art references contacting iscontinued until the desired amount of triiodide has reacted with thestrongly basic groups such that bacterially contaminated water isdisinfected when passed through a bed of the obtained resin. After asuitable contact time the iodine/resin is (water) washed to removewater-elutable iodine from the resin product.

However, as indicated in U.S. Pat. No. 4,238,477, it is difficult to usethe procedures outlined in the two previously mentioned U.S. patents soas to obtain a homogeneous iodine/resin product containing onlytriiodide anions and wherein all of the active sites of the resin havebeen converted to triiodide ions.

Accordingly, U.S. Pat. No. 4,238,477 teaches an alternate processwhereby the iodine/resin may be produced. In accordance with thisalternate impregnation/contact process, a suitable resin in the iodideform (I⁻) is contacted with water comprising diatomic iodine (I₂) insolution, the water being recycled between a source of a predeterminedamount of diatomic iodine and the resin. The process as taught by thislatter patent, however, is a relatively complicated system of pumps,vessels, heaters, etc.; by exploiting a fluidized bed, it in particularmay lead to a significant degree of resin bead attrition, i.e. particlebreakup.

The processes as taught in U.S. Pat. Nos. 3,817,860 and 3,923,665 arecarried out at ambient temperature and ambient pressure conditions. U.S.Pat. No. 4,238,477 teaches that the contact may occur at a highertemperature such as 60 to 95° C. but that the temperature must be anon-boiling temperature (with respect to water); see column 3 lines 55to 66.

The above referred to U.S. patents teach the use of the demanddisinfectant iodinated resins for treating water; see also U.S. Pat.Nos. 4,298,475 and 4,995,976 which teach water purification devices orsystems which exploit iodinated resins. None of these patents teachesthe use of the iodinated resins for the purpose of sterilizing air.

It is also known to use iodine tincture for sterilising wounds. Thesterilisation effect of iodine tincture is short lived; this means thatthe tincture must be reapplied on a regular basis to maintain thesterilisation effect. However, such solutions may also damage or destroythe tissue around the wound if applied too liberally and too often.

Additionally, the direct application of such solutions to a lesion orwound is usually accompanied by a painful sensation.

SUMMARY OF THE INVENTION

Accordingly it would be advantageous to have an iodine/resin productwhich has improved characteristics over known or commercially availableiodine/resin disinfectant products.

It would also be advantageous to have an alternate process for thepreparation of a iodine/resin product (which has improvedcharacteristics over the previously known iodine/resin).

It would be advantageous to have an alternative effective demanddisinfectant (e.g. bactericidal) resin and an effective technique forthe manufacture thereof. It would, in particular, be advantageous tohave an iodine/resin demand disinfectant having a relatively low levelof iodine bleed into a fluid (such as water or air) being treated aswell as an iodine impregnation process for obtaining such iodinatedresin.

It would also be advantageous to have a means whereby lesions, such asfor example wounds or burns, may be treated in order to facilitatehealing by devitalising microorganisms which may already be in the areaof the lesion and further to prevent microorganisms from having accessto such lesion (i.e. a dressing), i.e. to inhibit access from anyoutside biovectors such as for example airborne, waterborne, spitalborne, blood borne, particulate borne microorganisms and the like.

It would additionally be advantageous to have a means for inhibiting orpreventing microorganisms from contacting predetermined areas of thebody such as the skin (e.g. a protective textile for making protectiveclothing).

In accordance with a general aspect, the present invention provides aprocess for preparing an iodinated resin, said iodinated resin being aniodinated strong or weak base anion exchange resin, (i.e. a demand typeiodinated resin comprising polyiodide ions, having a valence of −1, theions being absorbed or impregnated into the resin as herein described)the process comprising a conversion step, the conversion step comprisingcontacting a strong or weak base anion exchange resin with a sufficientamount of an iodine-substance absorbable by the anion exchange resinsuch that the anion exchange resin absorbs said iodine-substance so asto convert the anion exchange resin to the iodinated resin, saidiodine-substance being selected from the group comprising I₂ (i.e.diatomic iodine) and polyiodide ions having a valence of −1, wherein forthe conversion step at least a portion of the absorption ofiodine-substance is effected at elevated temperature and/or at elevatedpressure, said elevated temperature being 100° C. or higher (e.g. atemperature higher than 100° C. such as, for example, 102° C., 103° C.,104° C., 105° C., 110° C. 115° C., 150° C., etc.), said elevatedpressure being greater than atmospheric pressure (e.g. a pressuregreater than barometric pressure such as for example 2 psig, 3 psig, 4psig, 5 psig, 15 psig, 25 psig, 35 psig, 100 psig, etc.).

In accordance with the present invention the iodinated resin may be onein which diatomic iodine is incorporated. The iodinated polyiodide-resinmay in particular be triiodide-resin. Thus, for example, theiodine-substance may comprise triiodide ion of formula I₃ ⁻, i.e. so asto form an iodinated resin which comprises (absorbed) triiodide ions offormula I₃ ⁻.

The terms “triiodide”, “triiodide ion” and the like, as used in thecontext herein, refer to or characterize a substance or a complex ascontaining three iodine atoms and which has a valence of −1. Thetriiodide ion herein therefore is a complex ion which may be consideredas comprising molecular iodine (i.e. iodine as I₂) and an iodine ion(i.e. I⁻). Similarly the terms “polyiodide”. “polyiodide ions” and thelike, refer to or characterize a substance or a complex as having threeor more iodine atoms and which may be formed if more of the moleculariodine combines with the monovalent triiodide ion. These terms are moreparticularly described in the above referred to U.S. patents.

In accordance with a further aspect, the present invention provides aprocess for preparing a demand iodinated resin, said iodinated resinbeing an iodinated strong or weak base anion exchange resin, (i.e. ademand iodinated resin comprising polyiodide ions having a valence of−1, the ions being absorbed or impregnated into the strong or weak baseanion exchange resin as herein described),

-   -   the process comprising a conversion step, the conversion step        comprising contacting a strong or weak base anion exchange resin        having an anion other than I⁻, with a sufficient amount of an        iodine-substance absorbable by the anion exchange resin such        that the anion exchange resin absorbs said iodine-substance so        as to convert the anion exchange resin to the iodinated resin,        said iodine-substance being selected from the group consisting        of polyiodide ions having a valence of −1,    -   wherein for the conversion step at least a portion of the        absorption of iodine-substance is effected at elevated        temperature and at elevated pressure, said elevated temperature        being 100° C. or higher (e.g. a temperature higher than 100°        C.), said elevated pressure being greater than atmospheric        pressure (e.g. a pressure greater than barometric pressure).

The strong or weak base anion exchange resin may be in a ionic form, forexample, a chloride or hydroxyl form, or in a free base form.

The conversion in accordance with the present invention may essentiallyor at least partially be effected at said elevated temperature andelevated pressure. The conversion, in accordance with the presentinvention, may, thus for example, be effected in one, two or morestages. For example, the elevated pressure/temperature conditions may bedivided between two different pairs of elevated pressure/temperatureconditions, e.g. an initial pressure of 15 psig and a temperature of121° C. and a subsequent pressure of 5 psig and a temperature of 115° C.

If the conversion is to be carried out in two stages, it may forexample, comprise a first stage followed by a second stage. The firststage may, for example, be effected at low temperature conditions (e.g.at ambient temperature and ambient pressure conditions) whereas thesecond stage may be effected at elevated conditions such as describedherein.

Thus, the present invention, in accordance with another aspect, providesa process for preparing a demand iodinated resin, said iodianted resinbeing an iodinated strong or weak base anion exchange resin, (i.e. ademand iodinated resin comprising polyiodide ions, having a valence of−1, the ions being absorbed or impregnated into the resin as hereindescribed),

-   -   the process comprising a conversion step, the conversion step        comprising contacting a strong or weak base anion exchange resin        with a sufficient amount of an iodine-substance absorbable by        the anion exchange resin such that the anion exchange resin        absorbs said iodine-substance so as to convert the anion        exchange resin to the demand iodinated resin, said        iodine-substance being selected from the group consisting of I₂        and polyiodide ions having a valence of −1,    -   wherein said conversion step comprises an initial conversion        stage followed by a second conversion stage, said initial        conversion stage comprising contacting the anion exchange resin        with the iodine-substance at a temperature of 100° C. or lower        so as to obtain an intermediate composition, said intermediate        composition comprising residual absorbable iodine-substance and        an intermediate iodinated resin, (i.e. a resin comprising        absorbed polyiodide ions having a valence of −1), and    -   wherein said second conversion stage comprises subjecting the        intermediate composition to elevated temperature and elevated        pressure, said elevated temperature being 100° C. or higher        (e.g. a temperature higher than 100° C.), said elevated pressure        being greater than atmospheric pressure.

In accordance with a further particular aspect, the present inventionprovides a process for preparing a demand iodinated resin, saiddisinfectant resin being an iodinated strong or weak base anion exchangeresin, (i.e. a demand iodinated resin comprising polyiodide ions, havinga valence of −1, the ions being absorbed or impregnated into the resinas herein described),

-   -   the process comprising a conversion step, the conversion step        comprising contacting a strong or weak base anion exchange resin        having an anion other than I⁻with a sufficient amount of an        iodine-substance absorbable by the anion exchange resin such        that the anion exchange resin absorbs said iodine-substance so        as to convert the anion exchange resin to the iodinated resin,        said iodine-substance being selected from the group consisting        of polyiodide ions having a valence of −1,    -   wherein said conversion step comprises an initial conversion        stage followed by a second conversion stage, said initial        conversion stage comprising contacting the anion exchange resin        with the iodine-substance at a temperature of 100° C. or lower        so as to obtain an intermediate composition, said intermediate        composition comprising residual absorbable iodine-substance and        an intermediate iodinated resin (i.e. a resin comprising        absorbed polyiodide ions having a valence of −1), and    -   wherein said second conversion stage comprises subjecting the        intermediate composition to elevated temperature and elevated        pressure, said elevated temperature being 100° C. or higher        (e.g. a temperature higher than 100° C.), said elevated pressure        being greater than atmospheric pressure.

In accordance with the present invention, for the first stage, the lowtemperature may, for example, be a non-boiling temperature of not morethan 95° C.; e.g. 15 to 60° C.; e.g. ambient temperature or roomtemperature such as a temperature of from about 15° C. to about 40° C.,e.g. 20 to 30° C. The pressure associated with the low temperaturecondition of the first stage may, for example, be a pressure of from 0(zero) to less than 2 psig; the pressure may in particular beessentially ambient pressure (i.e. a pressure of less than 1 psig to 0(zero) psig; 0 psig reflecting barometric or atmospheric pressure).

In accordance with the present invention, for the second stage, theelevated temperature may, for example, be: a temperature of 102° C. orhigher; e.g. 105° C. or higher; e.g. 110° C. or higher; e.g. 115° C. orhigher; e.g. up to 150° C. to 210° C.; e.g. 115° C. to 135° C. Theelevated pressure associated with the elevated temperature condition ofthe second stage may, for example, be: a pressure of 2 psig or greater;e.g. 5 psig or greater; e.g. 15 psig to 35 psig; e.g. up to 100 psig.

The present invention further relates to any demand iodinated resin, theiodinated resin being an iodinated strong or weak base anion exchangeresin which is the same as an iodinated strong or weak base anionexchange resin prepared in accordance with a process as defined herein;an iodinated resin the same as a resin prepared in accordance with the(particular) process described herein is one which has the same lowiodine bleed characteristic, i.e. the iodine is (more) tenaciouslyassociated with the resin than for previously known iodinated resins. Itin particular relates to a demand iodinated resin, the iodinated resinbeing an iodinated strong or weak base anion exchange resin wheneverprepared in accordance with a process as defined herein.

The present invention also relates to the use of iodinated resins todisinfect fluids containing microorganisms, such fluids including air,water, pus, and the like. The iodinated resin may for example be a knownresin such as discussed herein, a resin in accordance with the presentinvention, nylon based resin beads impregnated with iodine (such as MCVresin from MCV Tech. Intn'l Inc.), and the like.

Thus the present invention also provides a method for disinfecting aircontaining airborne microorganisms, said method comprising passing saidair over an iodinated resin such that airborne microorganisms contactsaid resin and are devitalized thereby. The iodinated resin may, forexample, be a demand iodinated resin. The iodinated resin may, forexample, comprise an iodinated strong or weak base anion exchange resin.

The present invention further provides a system for disinfecting aircontaining airborne microorganisms, said system comprising

-   -   means for providing an air path for the movement of air there        through, and    -   an iodinated resin disposed in said air path such that airborne        microorganisms in air passing through said air path are able to        be brought into contact with said resin and be devitalized        thereby,    -   said iodinated resin comprising an iodinated resin. The        iodinated resin may, for example, be a demand iodinated resin.        The iodinated resin may, for example, comprise an iodinated        strong or weak base anion exchange resin.        The present invention additionally provides a combination        comprising    -   an iodinated resin component, and    -   a carrier component, said iodinated resin component comprising        particles of an iodinated resin,    -   said particles of said iodinated component being held (e.g.        fixed) to said carrier component. The iodinated component may,        for example, be a demand iodinated component. The iodinated        resin may, for example, comprise an iodinated strong or weak        base anion exchange resin. The combination may be used as a        means for providing a barrier or shield for the body against        microorganisms. The combination may thus, for example, be        incorporated into a textile or other wearing apparel starting        material in the form of a layer (e.g. a liner layer). The        obtained raw wearing apparel material may then be used to make a        protective garment, glove, sock, footwear (e.g. shoe), helmet,        face mask and the like; the obtained wearing apparel nay be worn        in hazardous environments to protect the wearer from contact        with viable microorganisms. The combination as desired or as        necessary may flexible or stiff; depending on the nature of the        carrier component and also on the form of the resin (e.g. plate,        particle, etc.); the carrier component may comprise a (e.g.        flexible) polymeric matrix. The carrier component may comprise a        porous cellular matrix; particles of a demand iodinated resin        may be dispersed in a polymeric matrix. The iodinated strong or        weak base anion exchange resin may comprise a strong or weak        base anion exchange component which represents from 25 to 90        (e.g. 45 to 65) percent by weight of the total weight of the        iodinated resin.

The present invention in particular provides a combination comprising ademand iodinated component and a carrier component, said demandiodinated component comprising particles of an iodinated strong or weakbase anion exchange resin, said particles being held to said carriercomponent, said iodinated strong or weak base anion exchange resincomprising a strong or weak base anion exchange resin component whichrepresents from 25 to 90 percent by weight of the total weight of theiodinated strong or weak base anion exchange resin.

The present invention further provides a combination comprising a demandiodinated component comprising particles of an iodinated strong or weakbase anion exchange resin, and a carrier component comprising apolymeric matrix, said particles being dispersed in said polymericmatrix.

The present invention in a more particular aspect provides asterilisation dressing, for being applied to a lesion, (such as a sore,a wound (e.g. cut), an ulcer, a boil, an abrasion, a burn or otherlesion of the skin or internal organ), said dressing comprising

-   -   a iodinated resin component and    -   a carrier component,    -   said iodinated resin component comprising particles of an        iodinated strong or weak base anion exchange resin, said carrier        component being configured so as to hold onto particles of said        iodinated resin component such that microorganisms are able to        be brought into contact with said particles and be devitalised        thereby, said carrier component being of a pharmaceutically        acceptable material. The iodinated resin component may, for        example, be a demand iodinated resin. The iodinated resin may,        for example, comprise an iodinated strong or weak base anion        exchange resin. The carrier component may be stiff or it may be        flexible as desired. The (sterilization) dressing may, for        example, be applied over a wound or burn and be held in place        over the time period needed for the body to repair the damaged        area; the dressing during this time will act not only as a        barrier or shield to prevent infectious microorganisms from        contacting the lesion but also to sterilize the immediate area        around the lesion including sterilising any fluid exudate such        as pus which may exude from the lesion. Surprisingly, it has,        for example, been found that even with relatively prolonged        exposure of (guinea pig) skin to the active element of the        dressing (i.e. the demand iodinated resin) no irritation or        inflammation was noted. It has also surprisingly been found that        the dressing may effect infectious agents deep beneath the skin        or dressing. The healing process may thus be hastened by the        application of a (sterilization) dressing in accordance with the        present invention.

The demand iodinated resin for the above mentioned method and system fortreating air as well as for the combination and the dressing may be aniodinated resin produced in accordance with the present invention or itmay be a known demand iodinated resin such as for example as mentionedherein.

The demand iodinated resin depending on the intended use may take on anydesired form; it may be bulk form; it may be in sheet form; it may be inparticulate or granular form (e.g. particles of resin of from 0.2 mm to1 cm in size), etc.

It is to be understood herein, that if a “range” or “group ofsubstances” is mentioned with respect to a particular characteristic(e.g. temperature, pressure, time and the like) of the presentinvention, the present invention relates to and explicitly incorporatesherein each and every specific member and combination of sub-ranges orsub-groups therein whatsoever. Thus, any specified range or group is tobe understood as a shorthand way of referring to each and every memberof a range or group individually as well as each and every possiblesub-ranges or sub-groups encompassed therein; and similarly with respectto any sub-ranges or sub-groups therein. Thus, for example,

-   -   with respect to a pressure greater than atmospheric, this is to        be understood as specifically incorporating herein each and        every individual pressure state, as well as sub-range, above        atmospheric, such as for example 2 psig, 5 psig, 20 psig, 35.5        psig, 5 to 8 psig, 5 to 35, psig 10 to 25 psig, 20 to 40 psig,        35 to 50 psig, 2 to 100 psig, etc.;    -   with respect to a temperature greater than 100° C., this is to        be understood as specifically incorporating herein each and        every individual temperature state, as well as sub-range, above        100° C., such as for example 101° C., 105° C. and up, 110° C.        and up, 115° C. and up, 110 to 135° C., 115° C. to 135° C.,        102° C. to 150° C., up to 210° C., etc.;    -   with respect to a temperature lower than 100° C., this is to be        understood as specifically incorporating herein each and every        individual temperature state, as well as sub-range, below 100°        C., such as for example 15° C. and up, 15° C. to 40° C., 65° C.        to 95° C., 95° C. and lower, etc.;    -   with respect to residence or reaction time, a time of 1 minute        or more is to be understood as specifically incorporating herein        each and every individual time, as well as sub-range, above 1        minute, such as for example 1 minute, 3 to 15 minutes, 1 minute        to 20 hours, 1 to 3 hours, 16 hours, 3 hours to 20 hours etc.;    -   and similarly with respect to other parameters such as low        pressures, concentrations, elements, etc.

It is also to be understood herein that “g” or “gm” is a reference tothe gram weight unit; that “C” is a reference to the Celsius temperatureunit; and “psig” is a reference to “pounds per square inch gauge”.

BRIEF DESCRIPTION OF THE DRAWINGS

In drawings which illustrate example embodiments of the presentinvention:

FIG. 1 is a graph of showing the ppm of Iodine in the effluent versusthe total volume of water contacted with an iodinated resin bed of theprior art and an example iodinated resin of the present invention;

FIG. 2 is a graph of the number of microorganisms in effluent versus thetotal volume of contaminated water contacted with an iodinated resin ofthe prior art and an example iodinated resin of the present invention;

FIG. 3 is a perspective view of a cartridge which may be used to housean iodinated resin as described herein for use for example in a gasmask;

FIG. 4 is a cross sectional view 4-4 of the cartridge of FIG. 1;

FIG. 5 is a schematic illustration of a system for testing a cartridgecontaining an iodinated resin;

FIG. 6 is a schematic illustration of another type of system for testinga cartridge containing an iodinated resin;

FIG. 7 is a partially cut away perspective view of a sterilisationdressing of tea-bag type construction wherein the iodinated resinparticles are free flowing but are held together by being enveloped by afluid (e.g. air-liquid) permeable envelope of paper, gauze, plasticsmaterial, etc.;

FIG. 8 is a perspective view of a band-aid type sterlization dressing,wherein the iodinated resin particles are fixed to a central portion ofan outer surface of a flexible band-aid carrier;

FIG. 9 is a perspective partially cut away view of a sterilisation foamor sponge type dressing comprising a flexible foam matrix havingiodinated resin particles dispersed therein, the foam matrix having arelatively small pore size structure;

FIG. 10 is a perspective partially cut away view of a sterilisation foamor sponge type dressing comprising a flexible foam matrix havingiodinated resin particles dispersed therein, the foam matrix having arelatively large pore size structure; and

FIG. 11 is a cross sectional view of a sandwich type of textile materialfor use in the preparation of protective clothing, the textile includinga layer of a flexible foam matrix such as is shown in FIG. 10.

DETAILED DESCRIPTION OF THE INVENTION

In accordance with the present invention, the elevated temperature mayas mentioned above, for example, be in the range of from 105° C. to 150°C.; the elevated pressure may be 5 psig and up.

In accordance with the process of the present invention the anionexchange resin may be a strong base anion exchange resin, such as aquaternary ammonium anion exchange resin, or a weak base anion exchangeresin, such as a primary, secondary or tertiary amine anion exchangeresin. The anion exchange resin may be in the chloride form Cl⁻, in thehydroxyl form OH⁻; etc.

In accordance with the present invention the obtained iodide-resin maybe treated prior to use to remove any water-elutable iodine from theiodide-resin. The treatment (e.g. washing) may be continued until nodetectable iodine is found in wash water (the wash water initially beingion free water). Any suitable (known) iodine test procedure may be usedfor iodine detection purposes (see for example the above-mentioned U.S.patents).

In accordance with the present invention, the absorbable iodinesubstance may, for example, be provided by a composition comprising amixture of KI, I₂ and a minor amount of water, the mole ratio of KI toI₂ initially being about 1; the expression “minor amount of water” asused herein shall be understood as characterizing the amount of water asbeing sufficient to avoid I₂ crystallization.

The present invention in a further aspect provides an enhancediodine/resin demand iodinated product in which more iodine may bedistributed throughout and be more tenaciously associated with the resin(e.g. beads) than with the previously known or commercially availabletechniques, the iodinated resin being produced by a process as describedherein. The invention more particularly provides an enhancedtriiodide-resin.

The present invention can be practised with any anion exchange resin.Each anion exchange resin is classified as strong or weak according tothe ionizing strength of the functional group.

Strong base anion exchange resins are described in more detail in theabove-mentioned United States patents such as U.S. Pat. No. 3,923,665. Aquaternary ammonium anion exchange resin is, however, preferred. As usedherein, it is to be understood that the expression “strong base anionexchange resin” designates a class of resins which either containstrongly basic “cationic” groups, such as quaternary ammonium groups(—NR₃ ⁺, where each R may be the same or different group, for example analkyl or aryl group) or which have strongly basic properties which aresubstantially equivalent to quaternary ammonium exchange resins. U.S.Pat. Nos. 3,923,665 and 3,817,860 identify a number of commerciallyavailable quaternary ammonium resins, as well as other strong baseresins including tertiary sulphonium resins, quaternary phosphoniumresins, alkyl pyridinium resins and the like.

Commercially available quaternary ammonium anion exchange resins whichcan be used in accordance with the present invention include inparticular, Amberlite IRA-401 S, Amberlite IR-400 (Cl⁻), AmberliteIR-400 (OH⁻), Amberlite IR-402 (Cl⁻), etc., (from Rohm & Hass) which maybe obtained in granular form. These resins may for example, containquaternary ammonium exchange groups which are bonded to styrene-divinylbenzene polymer chains.

As used herein, it is to be understood that the expression “weak baseanion exchange resin” designates a class of resins which either containweakly basic cationic groups or which have weakly basic properties whichare substantially equivalent to primary, secondary or tertiary amines.Weak anion exchange resins are mostly of the amine type. These includeresins which have as functional groups a primary amine (—NH₂), asecondary amine (—NHR, where R may be, for example, an alkyl or arylgroup) or a tertiary amine (—NR₂, where each R may be the same ordifferent group, for example an alkyl or aryl group), or mixturesthereof. Suitable functional groups include, for example, aminoethyl,dimethylaminoethyl, diethylaminoethyl and similar groups.

Commercially available weak base anion exchange resins which can be usedin accordance with the present invention include those marketed, forexample, under the trade names of LEWATIT (manufacturer Bayer Ag); DOWEX(manufacturer Dow Chemical); DIAION, NEKROLITH and RELITE (manufacturerMitsubishi Chemical); PUROLITE (manufacturer Purolite); AMBERLITE,AMBERLYST and DUOLITE (manufacturer Rohm and Haas); SERDOLIT(manufacturer Serva Heidelberg GmbH); IONAX (Manufacturer SybronChemicals Inc.); and FINEX (manufacturer Finex-FX Oy). Examples of weakbase anion exchange resin include Purolite A845, Dianon WA10, AmberliteIRA67, Amberlite IRA68, and Amberlyst A-21.

The resins which may be used herein may be in a hydroxyl form, achloride form or in another salt (e.g. sulphate) form provided that theanion is exchangeable with the iodine member (e.g. with triiodide ion).

The starting resin may, for example, be granular (i.e. comprise aplurality of particles) such that the final product will likewise have agranular or particulate character; the granular form is advantageous dueto the high surface area provided for contact with microorganisms. Thestarting resin may, for example, comprise granules having a size in therange of from 0.2 mm to 0.8 cm (e.g. of from 0.35 mm to 56 mm).

Commercially available resins such as those mentioned above areavailable in the salt form (e.g. as the chloride) and in the form ofporous granular beads of various mesh sizes; the resin may of course beused in a bulk or massive form such as a plate, sheet, etc.

In accordance with the present invention, for example, a resin may beconverted from a non-iodide form (e.g. a chloride form, a sulphate form)to the I₃ ⁻form. Suitable halide salts include alkali metal halides(such as KI, NaI, . . . ); potassium iodide is preferred. Alternatively,an iodide form of the resin may be used and the resin contacted with asource of diatomic iodine.

In accordance with the present invention any material or substancecapable of donating an iodine-member absorbable by the anion exchangeresin so as to convert the anion exchange resin to the desiredpolyiodide-resin may be used, as long as the denotable iodine-memberthereof is a polyiodide ion having a valence of −1 and/or diatomiciodine. Examples of such materials in relation to iodine are shown inthe above mentioned U.S. patents; e.g. compositions comprising iodine(I₂) and alkali metal halide (KI, NaI, etc., KI being preferred) inassociation with water. Alternatively, if the resin is in an iodide saltform (I⁻¹), the material may comprise the corresponding iodine ingaseous form.

Thus, for example, if a triiodide-resin is desired the resin may becontacted with an alkali metal iodide/I₂ mix wherein the iodide and thediatomic iodine are present in more or less stoichiometric amounts (i.e.a mole ratio of 1); see the previously mentioned U.S. patents. Byapplying stoichiometric amounts of the iodine ion and iodine molecule(i.e. one mole of I₂ per mole of I⁻¹), the iodide sludge will comprisesubstantially only the triiodide ions. If stoichiometric excessquantities of I₂ are used some of the higher polyiodide ions may beformed. Preferably, no more than the stoichiometric proportions of I⁻and I₂ are used in the initial aqueous starting sludge so thatsubstantially only triiodided attaches to the resin.

For example iodine may be combined with sodium, potassium or ammoniumiodide and some water. The composition will contain monovalent iodineion which will combine with diatomic iodine (I₂) to form polyiodide ion.The molar ratio of iodine ion to diatomic iodine will dictate the natureof the polyiodide ion present, i.e. triiodide ion, mixtures of triiodideion and other higher polyiodides ions, pentaiodide ion, etc. Using about1 mole of iodine ion per mole of diatomic iodine the formation oftriiodide ion will be favoured. If stiochiometric excess of diatomiciodine is used this will favour the formation of higher polyiodides.

The determination of the (total) amount of iodine to be contacted withthe resin, residence times etc., will depend upon such factors as thenature of the polyiodide it is desired to introduce into the structureof a resin; the nature of the starting resin (i.e. porosity, grain size,equivalent exchange capacity of the resin, etc.), etc. Thus, forexample, to determine the amount of iodine required to prepare apolyiodide resin, the equivalent exchange capacity of the resin needs tobe known. If necessary, this can be readily determined for example bythe procedure described in U.S. Pat. No. 3,817,860 (column 9, lines 15to 28). The components of the process may be chosen such that theobtained iodinated strong or weak base anion exchange resin may comprisea strong or weak base anion exchange resin component which representsfrom 25 to 90 (preferably 45 to 65) percent by weight of the totalweight of the obtained iodinated resin.

The conversion at elevated conditions, in accordance with the presentinvention, may be effected in a reactor which is pressure sealableduring conversion but which may be opened for recovery of the resinproduct after a predetermined reaction time. The process may thus be abatch process wherein conversion at elevated temperature and pressure iseffected once the reactor is sealed. In accordance with the presentinvention the reactor may be sized and the amount of reactantsdetermined so as to provide a void space in the reactor during reaction.In the case, for example, wherein the material having the denotableiodine-member is a sludge of alkali metal/I₂ and water, the weight ratioof sludge to resin may be 1:1 or higher, e.g. 1:1 to 5:1; a weight ratioof 1:1 (if Amberlite 401-S is used as the resin) is preferred so as tominimize the amount of unabsorbed iodine which must be washed from theiodine/resin product.

The high temperature/pressure contact conditions may as mentioned abovebe chosen with a view to maximizing the iodine content of the obtainediodine (e.g. iodine) demand resin.

In accordance with the present invention conversion of the resin to apolyhalide (e.g. I.₃ ⁻) form may be effected at elevated temperaturegreater than 100° C., for example in the range of 105° C. to 150° C.(e.g. 110-115° C. to 1500° C.); the upper limit of the temperature usedwill, for example, depend on the characteristics of the resin beingused.

As mentioned in order to effect the conversion at elevated pressure, theconversion may take place in a closed vessel or reactor. The pressure insuch case may be a function of the temperature such that the pressuremay vary with the temperature approximately in accordance with the wellknown gas equation PV=nRT, wherein V=the constant (free) volume of thereactor, n=moles of material in the reactor, R is the universal gasconstant, T is the temperature and P is the pressure. In a closedvessel, the temperature of the system may therefore be used as a meansof achieving or controlling the (desired) pressure in the vesseldepending upon the makeup of the Iodine mix in the reactor. Thus inaccordance with the present invention, a reaction mix disposed in apressure sealed reactor may be, for example, subjected to a temperatureof 105° C. and a pressure of 200 mmHg, the pressure being induced bysteam.

Alternatively, a relatively inert gas may be used to induce and/oraugment the pressure in the reactor. Thus, a pressurized relativelyinert gas may be injected into a sealed reactor. The chosen gas must notunduly interfere with the production of a suitable iodinated resin. Thehigh temperature/pressure treatment may be conducted in a closed reactorin the presence of (trapped air), a non-interfering gas such as iodineitself or of some other relatively inert (noble) gas; the pressure asmentioned above may be augmented by the pressuring gas. Air, carbondioxide, nitrogen or the like may also be used as a pressuring gas, ifdesired, keeping in mind, however, that the use thereof must not undulyinterfere with the production of a suitable iodinated resin. If pressureis to be induced by steam then as mentioned below steps should be takento isolate the reaction mix from (excess) water.

In accordance with the present invention, the elevated pressure is anypressure above ambient. The pressure may, for example, be 1 psig orhigher, e.g. in the range from 5 to 50 psig; the upper limit of thepressure used will also, for example, depend on the characteristics ofthe resin being used.

The residence or contact time at the elevated conditions is variabledepending upon the starting materials, contact conditions and amount of(tenaciously held) iodine it is desired to be absorbed by the anionexchange resin. The contact time may thus take on any value; usually,however, it is to be expected that it will be desired that the contacttime (under the conditions used) be sufficient to maximize the amount of(tenaciously held) iodine absorbed from the material containing theabsorbable iodine moiety. The residence time may for example be aslittle as 5 to 15 minutes (in the case where a preimpregnation step isused as shall be described below) or several hours or more (up to 8 or 9hours or more). The residence time exploited for elevated theconditions, in any event, will as mentioned above depend on the startingmaterial, temperature and pressure conditions, etc.; it may vary fromseveral minutes to 8 or 9 hours or more; the upper time limit will inany event also, for example, depend on the characteristics of the resinbeing used.

Preferably, the contact at high temperature/pressure is preceded by aninitial impregnation or absorption step (first stage). Such first stagemay be carried out for only a few minutes (e.g. for from 1 to 10 minutesor more) or for up to 24 hours or more (e.g. for from one hour or morei.e. for from three to twenty-four hours). The time period of theinitial stage may be relatively short. The time period, for example, maybe a few minutes or so and may correspond to the time necessary to justmix the reactants together; in this case the conversion may beconsidered to be essentially carried out in a single stage at elevatedconditions. The residence time of the first stage will also bepredetermined with a view to the end product resin desired. For example,a water containing sludge of triiodide ions can be contacted with a saltform of the starting resin at ambient (i.e. room) temperature andpressure conditions to obtain an intermediate iodide-resin reactionproduct including residual iodine-substance. This step is preferablycarried out in a batch reactor; the obtained intermediate compositioncomprising an intermediate iodide-resin may then be subjected to thehigher temperature and pressure in accordance with the present inventionin batch fashion as well. Such a first stage may be used to initiatebuildup of iodine within the resin matrix.

In accordance with the present invention a demand iodide-resin may, forexample, be obtained by

-   -   a) bringing a porous, granular, starting resin into contact with        an aqueous sludge of iodine and potassium iodide so as to obtain        a paste mixture, iodine being present in the sludge essentially        as triiodide ions, said starting resin being a strong or weak        base anion exchange resin having strongly or weakly basic groups        thereof in a salt form the anion of which is exchangeable with        triiodide ions,    -   b) subjecting the paste mixture to elevated temperature and        pressure conditions in an enclosed container or reactor (e.g.        autoclave) for a predetermined impregnating duration of time, a        void space being provided in the reactor such that contact        occurs under an (essentially) iodine (rich) atmosphere, and    -   c) washing the obtained iodide-resin product (with a suitable        (i.e. purity) washing liquid, (e.g. deionised water, R/O water        (at 45° C.), etc.) to remove water elutable iodine such as KI        from the surface of the resin so that on drying no iodine (KI)        crystals will form on the surface of the iodine/resin; RIO        water, is water obtained using double reverse osmosis. R/O water        is defined below.

More particularly a demand iodide/resin may be obtained using thefollowing sequence of steps:

-   -   1. The resin is purified by triple passage of water and then        disposed in ethanol in an electrosonic bath and flushed with        water and drip dried;    -   2. (Essentially) stoichiometric amounts of I₂ and potassium        iodide are admixed with a minimum amount of water which is just        sufficient to obtain an I₃ ⁻slurry or sludge (with, if desired,        very low heating);    -   3. The resin is admixed with the above-minimal water slurry in        small aliquats so as to obtain a predetermined weight ratio of        slurry to resin (e.g. a 50:50 weight ratio);    -   4. The resin-slurry mixture is then placed in a shaking bath at        atmospheric pressure in a closed, air-tight container (if        necessary the container being provided with a small pressure        release valve or opening the purpose of which will be        hereinafter explained) for a predetermined time period (e.g. for        up to, for example, sixteen to twenty-four hours or more [e.g. a        week if desired]) to form an intermediate resin composition;    -   5. The container containing the reaction mixture is then        disposed in a (steam) autoclave and heated at high temperature,        (e.g. 120° C.) to provide a super atmospheric pressure therein        (with the small valve open if the container walls would not be        able to resist the pressure to be exerted within the autoclave)        for a predetermined residence time (e.g. a residence time of        about fifteen minutes) calculated from the time the mixture        reaches the predetermined high temperature (e.g. 120° C.).    -   6. The autoclave is removed from the heat and as soon as the        pressure is equalized to atmospheric, the internal container is        removed and the resin product is washed (e.g. six times) with        R/O water until the wash water comes out with a total iodine        content of less than 0.1 parts per million.

A small hole is necessary when a container such as a glass flask is usedin order to avoid a too great pressure difference being built up betweenthe interior of the flask and the interior of the autoclave which mightcause the flask to collapse. The hole in any event is just large enoughto more or less allow for the equalization of pressure and to maintain apositive pressure in the flask relative to the interior of the autoclavesuch that any foreign material such as water vapour is inhibited fromflowing into the flask. A more sturdy pressure resistant container couldof course be used such that, depending on the construction of thecontainer and the temperature/pressure conditions prevailing in theautoclave, the hole may be avoided. Alternatively, instead of using aseparate container to hold the reaction mix and placing it in a separateautoclave, a single autoclave/container may be used serving to hold andheat the reaction mix under pressure; such a container must of course beconstructed so as to be able to resist the predetermined reactionconditions.

The iodide-resin compound formed as described herein can be used as ademand disinfectant to disinfect water by batch contacting thecontaminated water with the resin; continuous processing as mentioned inU.S. Pat. No. 3,923,665 is also possible. Thus water containing viablebacteria (to be killed) may be passed through a fixed bed of porousgranular iodine/resin material. The maximum permissible flow rates fortotal bacterial sterilization may vary with the concentration of thepolyiodide (e.g. triiodide) groups in the resin, bed depth, bacterialcount, etc. The disinfection process may be monitored by taking samplesof water after passage through the bed. Potable innocuous water may thusbe readily produced in accordance with the present invention without theincorporation of objectionable amounts of free iodine therein as aresult. The resin may be used with any (known) water treating devicessuch as for example those shown in U.S. Pat. Nos. 4,749,484 and4,978,449.

In accordance with a further aspect, however, as mentioned above, thepresent invention also provides a method for disinfecting air containingairborne microorganisms. The method may comprise passing the air over ademand iodinated resin such that airborne microorganisms contact saidresin and are devitalized thereby, the demand iodinated resin comprisingan iodinated strong or weak base anion exchange resin. The method may,for example, include passing the air through a bed of granules ofiodinated resin so that the air courses over the granules (in aserpentine manner) as the air makes its way through the bed. The maximumpermissible flow rates for total bacterial sterilization may vary withthe concentration of the polyiodide groups in the resin, bed depth,bacterial count, etc. The iodinated strong or weak base anion exchangeresin may comprise a strong or weak base anion exchange resin componentwhich represents from 25 to 90 (preferably 45 to 65) percent by weightof the total weight of the iodinated resin.

In accordance with an additional aspect, the present invention providesa system for disinfecting air containing airborne microorganisms, saidsystem, for example, comprising

-   -   means for providing an air path for the movement of air there        through, and    -   a demand iodinated resin disposed in said air path such that        airborne microorganisms in air passing through said air path are        able to be brought into contact with said resin and be        devitalized thereby,    -   said demand iodinated resin comprising an iodinated strong or        weak base anion exchange resin.

An air path means may define an air inlet and an air outlet. The resinmay be disposed between said inlet and outlet or be disposed at theinlet or outlet. The air path means may take any form. It may take theform of ductwork in a forced air ventilation system with the demandiodinated resin comprising a bed of resin granules through which the airis made to pass, the bed otherwise blocking off the air path.Alternatively the air path means may be defined by a cartridge used fora gas mask, the cartridge having an inlet and an outlet for air; theiodinated resin for the cartridge may, if desired, be present as a bedof granules, granules incorporated into a (fluid) porous carrier (e.g.tissue, polyurethane foam, etc.) or alternatively take a more massiveform such as a plate(s), a tube(s), a block(s), etc. Cartridge type gasmasks are known; such gas masks may be obtained for example from EasternSafety Equipment Co., Mosport, N.Y. USA.

The C50 cartridge from a gas mask (from Glendale Protecting TechnologiesInc. Woodbury, N.Y. USA) may for example be adapted to hold a bed ofresin of granules of the present invention. Referring to FIG. 3, thecartridge 1 comprises an a hollow, open ended, thin-walled, tubular bodyof circular cross section. The wall 2 may for example be of nylon. Theopen ends of the cartridge are each blocked off by some suitable meshlike support material 3 (e.g. 10 micron polypropylene mesh) which isheld in place in any suitable known manner such as by glues, springclip, etc.; the mesh support shown in FIG. 3 has the reference numeral3. Referring to FIG. 4, the iodinated granular resin bed 4 occupies theentire space between the mesh supports 3 and 3′; although the granularresin is more or less tightly packed between the mesh supports 3 and 3′,there are still air spaces between the granules for the passage of airthrough the granular bed. The mesh supports each have openings smallenough to retain the iodinated resin in place while allowing air to passthere through into the and through the supported resin bed 4. Thecartridge as shown in FIG. 4 may include a downstream bed 5 of granulesof activated carbon, catalyst, or iodine absorbent resins, to scavengeany iodine liberated from the iodinated resin 4. The activated carbonbed 5 is held in place by a mesh support 3′ and an additional mesh 6.The bed depth of the resin and carbon is shown as about 2.5 cm; wherasthe bed diameter is about 8 cm. If the iodinated resin made inaccordance with the process of the present invention is used the carbonbed may be omitted, i.e. only the iodinated resin bed 4 may be presentin the cartridge as the active component (in the examples below, unlessthe contrary is indicated, the cartridges do not include any carbonbed); in this case the bed depth may, for example, be less 2.5 cm, e.g.0.1 cm, 0.25 cm, 0.5 cm, 0.85 cm, 1.15 cm, etc. Such a cartridge may bedisposed in an air path as shown for example in FIGS. 5 and 6 which willbe discussed below.

The resin disposed in the air path could of course take on any formother than granules such as blocks, plates, tubes etc.

The iodinated demand iodinated resin for air treatment may be any(known) iodinated resin so long as the iodinated resin is capable ofdevitalizing airborne microorganisms (i.e. microorganisms transported byair) coming into contact therewith. It may, for example, be a resin asproposed in U.S. Pat. Nos. 3,923,665 and 4,238,477; in this case,however, it may be necessary to use the resin in conjunction with aniodine scavenging material if the resin gives up too much iodine to theair. The iodine scavenging material may be an activated carbon materialor an un-iodinated strong or weak base anion exchange resin as describedherein.

Alternatively, as mentioned above, iodinated resin may advantageously bea resin made in accordance with the present invention; in this case theresin need not be used in conjunction with an iodine scavenging materialsuch as a (known) exchange resin, activated carbon, catalyst, etc.,since an iodinated resin made in accordance with the process of thepresent invention may liberate iodine into the air in an amount belowacceptable threshold limits for breathing by human beings.

If desired the iodinated resin for the treatment of air or water may besome type of mixture of iodinated resins, e.g. a mixture of a knowniodinated resin and an iodinated resin prepared in accordance herewith.

As mentioned above, the present invention in a further aspect provides acombination which may act as a sterilization barrier with respect tomicroorganisms. The sterilization combination may, for example, beincorporated into protective wearing apparel or be configured as asterilization dressing for lesions such as for example, wounds andburns; the sterilisation barrier combination can be configured to be ornot to be air breathable.

A sterilization dressing of the present invention advantageously maytake the form of a flexible porous cellular polymeric foam sheet havinga spongy aspect and having dispersed within the polymeric matrix thereofparticles of a demand iodinated resin comprising a (known) iodinatedresin or an iodinated resin as described herein. The sterilization sheetmay be placed over a burn area to maintain the burn area in a sterilizedstate during the healing process. The iodinated resin particles aredistributed throughout the polymeric matrix and have surfaces projectinginto the open pores of the spongy matrix; the spongy matrix acts as asponge so that on the body side thereof it can soak up fluid such as puswhich exude from the burn lesion. Once within the body of the matrix anymicroorganisms in the fluid or pus can contact the iodinated resinparticles and become devitalized as a result. On the other hand, anymicroorganisms on the opposite side of the sterilization barrier whichattempt to pass through the barrier are also subject to being contactedwith the iodinated resin and are also devitalised.

A (flexible) phamaceutically acceptable hydrophilic foam matrix may beobtained by reacting water with HYPOL (trademark) foamable hydrophilicpolyurethane polymer; the HYPOL polymer starting material may beobtained from W. R. Grace & Co. Lexintington Mass. U.S.A. Water reactsto cross link the HYPOL polymer; if water is added quickly or atrelatively high temperature foaming occurs and a foam product isobtained.

The carrier component may, as necessary, also be oil or fat loving, e.g.for dealing with individuals with high cholesterol levels.

If desired the iodinated resin for the sterilisation combination may besome type known iodinated resin, a resin prepared in accordanceherewith, or a mixture of iodinated resins, e.g. a mixture of a knowniodinated resin and an iodinated resin prepared in accordance herewith.

FIGS. 7 to 11 which illustrate a number of example embodiments ofsterilisation barrier combinations of the present invention will bediscussed below; these combinations are also described in example 15below.

Turning back to the process of the present invention, if commerciallyavailable materials are to be used to make the iodine/resin then,depending on the purity thereof, the starting materials may have to betreated to remove components which may interfere with the absorption ofthe halide into the resin. Water if present in the initial reaction mixshould be free of interfering elements such as interfering ions.Distilled or ion free water is preferably used for washing.

The following materials may be used to prepare a triiodide resin inaccordance with the present invention:

-   -   a) Amberlite 401-S (from Rohm & Hass) a strong base anion        exchange resin in granular form, having the following        characteristics:    -   support matrix—styrene/divinyl benzene polymer    -   anion—chlorine    -   density—1.06    -   effective size (diameter)—0.52 mm    -   total exchange capacity—0.8 meq/ml    -   working Ph range—0 to 11    -   moisture content—62%    -   working temperature-170° F. or less    -   b) I₂ (solid)—U.S.P. grade (from Fisher Scientific)    -   c) Potassium iodide (KI)—U.S.P. grade (from Fisher Scientific)    -   d) Water—ultra pure: obtained using double reverse osmosis (i.e.        herein sometimes referred to simply as R/O water)    -   e) Ethanol—U.S.P. grade (from Fisher Scientific)

Using the above substances a resin crammed with triiodide (i.e. atriiodide jam-backed resin) may be obtained as indicated in thefollowing examples.

For the following examples, the following procedure for the evaluationof iodine (I₂) and Iodide (I⁻), was conducted according to “standardmethods for the examination of water and wastewater 17e Ed.”:

Iodine Method:

mercuric chloride added to aqueous elemental iodine solutions causescomplete hydrolysis of iodine and the stoichiometric production ofhypoiodous acid. The compound 4,4′,4″methylidynetris (leuco crystalviolet) reacts with the hypoiodous acid to form crystal violet dye. Themaximum absorbance of the crystal violet dye solution is produced in thePh range 3.5-4.0 and measured at a wavelength of 592 nm. The absorbancefollows beers' law over a wide range of iodine concentration. Iodine canbe measured in the presence of max. 50 PPM iodide ions withoutinterference.

Iodide Method:

iodide is selectively oxidized to iodine by the addition of potassiumperoxymonosulfate. The iodine produced reacts instantaneously with theindicator reagent leuco crystal violet over the same conditionsdescribed previously for iodine methods. Total iodine+iodide resultsfrom this procedure and iodide is calculated from substraction of iodineconcentration.

Readings were performed on a 1 kb spectrophotometer with a lightpath of1 cm and selected at 592 nm.

EXAMPLE 1

Starting Materials Pretreatment

i) Resin

The resin is water washed to remove undesirable elements such asmaterial in ionic form. Thus, 100.00 grams of Amberlite 401 S and 200 mlof R/O water are placed in an erlenmyer of 1000 ml. The mixture isshaken for about 3 minutes and the water is then separated from theresin by drip filtration using a wathman filter paper and funnel. Theresin is water washed in the same fashion two more times. After the lastwater wash the resin is drip dried (i.e. again using a wathman filterpaper and funnel) for 15 minutes. The so recovered water washed resin issubjected to an alcohol wash to dissolve undesirable organic materialthat may be stuck on the resin. Thus, the water washed resin is immersedin 300.00 ml of ethanol. The resin alcohol mixture is shaken in anultrasonic bath (Crest ultrasonic: 1000 Watts—20 liter capacity) for 5minutes. The alcohol washed resin is drip dried, again using a wathmanfilter paper and funnel. The “fish” smell is removed from the alcoholwashed resin by a final water washing stage wherein the wash R/O wateris preheated to 40 degrees Celsius. The alcohol washed resin is placedin an Erlenmeyer flask (1000 ml) and 250 ml of R/O water at 40 degreesCelsius is added thereto. The water-resin mixture is shaken in a shakingbath (Yamata shaking bath—1 impulse per second/water at 32 degreesCelsius) for 5 minutes; the water is then removed from the resin by dripdrying as mentioned above. The water wash is repeated once more and theresin is drip dried (for 1 hour) as mentioned above. The washed resin isnow ready for use in example 2 herein below.

ii) Iodine Sludge Containing Water

A mixture of iodine (I₂) and potassium iodide (KI) is prepared by mixingtogether, in an Erlenmeyer flask, 60.00 grams of iodine and 40.00 gramsof potassium iodide (in both cases on a dry weight basis). ThereafterR/O water is admixed slowly drop-by-drop with the mixture until ametallic looking sludge is obtained (e.g. with the addition of about5.00 grams of water). The obtained iodine/potassium iodide sludge isthen ready for use in example 2 herein below.

EXAMPLE 2

Low Temperature/Pressure Preimpregnation of Resin with Iodine

The aqueous iodine sludge, as obtained above, is placed in a 500.00 mlErlenmeyer flask and is slowly heated to, and maintained at 40 degreesCelsius for a few minutes. Once the temperature of the sludge reaches40° C., the washed resin, obtained as above, is slowly admixed with theiodine sludge in 10.00 gram portions every 8 minutes until all of thewashed resin is within the Erlenmeyer flask. The 500 ml Erlenmeyerflask, containing the obtained starting mix (comprising the I₂/KImixture and the washed resin—approximately 100 grams of each of thestarting materials), is then sealed with a cork and is placed in ashaking water bath (Yamato BT:−25) for a period of 16 hours. Thetemperature of the water in the shaking bath is maintained at about 20degrees Celsius during this time period. At the end of the time period,the Erlenmeyer flask is removed from the shaking bath; at this point theremoved flask contains an preimpregnation mix comprising impregnatedresin and remaining I₂/KI. The Erlenmeyer flask is sized such that atthe end of this (initial) impregnation step, it is only 50% filled withthe in process resin, etc, i.e. there is a void volume above theimpregnation mix. NOTE: If processing of the treated resin is stopped atthis point and the obtained resin is suitably washed, a resin isobtained in accordance with the prior art i.e. U.S. Pat. No. 3,923,665.

EXAMPLE 3

Elevated Pressure/Temperature Treatment

The cork of the Erlenmeyer flask of EXAMPLE 2 removed from the shakingbath and including the obtained impregnation mix comprising impregnatedresin and remaining I₂/KI, is changed for a cork having a small diameterperforation passing there through (i.e. of about 3 mm in diameter). Withthe perforated cork in place, the Erlenmeyer flask is disposed within a(steam pressure) autoclave along with a suitable amount of water. Withthe autoclave (pressure) sealed about the flask, the autoclave isheated. Heating proceeds until an internal temperature and pressure of115 degrees Celsius and 5 psig respectively is reached. Once thoseparameters have been reached, they are maintained for 15 minutes ofprocessing time. Thereafter the autoclave is allowed to slowly cool for50 minutes of cooling time (until the internal pressure is equal toambient pressure) before removing the Erlenmeyer flask containing a(raw) product iodinated resin in accordance with the present invention.

EXAMPLE 4

Washing of Raw Product Resin

The (raw) iodinated resin of Example 3 is removed from the autoclaveErlenmeyer flask and placed in another 2000 ml Erlenmeyer flask. 1400 mlof R/O water at 20 degrees Celsius is admixed with the resin in theflask and the slurry is shaken manually for 3 minutes. The wash water isthereafter removed from the flask by decantation. This wash step isrepeated 7 more times. The entire wash cycle is repeated twice (i.e.eight water washes per cycle) but using water at 45 degrees Celsius forthe next wash cycle and then with water at 20 degrees Celsius for thelast wash cycle. The washed iodine-resin is then ready to use.

EXAMPLE 5

Comparative Physical Data

The following resins were examined with respect to certain physicalcharacteristics:

Resin I-A

Iodinated resin manufactured in accordance with the present inventioni.e. as obtained from example 4 above.

Resin I-B

Iodinated resin manufactured in accordance with teachings of the priorart (i.e. U.S. Pat. No. 3,923,665), namely as obtained from example 2above after suitable washing to remove elutable iodine.

Resin I-C

Iodinated resin manufactured by Water Technology Corporation inMinneapolis (a triiodide based iodinated resin).

Resin I-D

Iodinated resin manufactured by Water Technology Corporation inMinneapolis, sold under the Trademark: Pentapure.

In the examples which follow the above resins will be referred to usingthe above designations, i.e. I-D, Resin I-A, etc.

EXAMPLE 5.1

Comparative Wet Tap Density

The resins were examined in a drip dried state, i.e. the resins wereused after being drip dried using wathman filter paper and a funnel (fora 5 minute dry period). 25 ml and 100 ml flasks were used for the study.The flasks were weighed empty. The flasks were then filled with resinand were then subjected to a manual vibration sequence (approximately 2impulses per second for two minutes) in order to settle the resin, thevolume of the settled resin was then noted. The density was obtained byweighing a filled flask and subtracting the weight of the empty flask soas to obtain the weight (grams) per unit volume (ml) of the resin. Theresults are shown in Table 1 below.

TABLE 1 Resin Density I-A 1.720 gm/ml I-B 1.480 gm/ml I-D 1.600 gm/ml

EXAMPLE 5.2

Comparative Dry Tap Density

The same procedure as described above for example 5.1 was used exceptthat the initial resin materials were dried simultaneously for 12 hoursat 55 degrees Celsius, and placed in desiccant for 2 hours duringcooling. The results are shown in Table 2 below.

TABLE 2 Resin Density I-A 1.088 gm/ml I-B 0.957 gm/ml I-D 1.016 gm/ml

EXAMPLE 5.3

Iodine Content

1.0 gm of each of the different resins was boiled in 20 ml of water witha concentration of 5% by weight of sodium thiosulphate. Boiling wasconducted for 20 minutes where after the water mixture was set aside toair cool for 12 hours. The resin was then recovered and washed with 50ml of a boiling water solution of sodium thiosulphate. Thereafter theresin was dried in an oven for 12 hours at 105 degrees. The iodinedesorbed resin was weighed in each case and the weight difference wasused to calculate the % by weight of the initial resin represented bythe active iodine removed. The results are shown in Table 3 below.

TABLE 3 Resin % by weight iodine I-A 43.7% I-B 32.4% I-C 30.7% I-D 36.7%NOTE: As may be seen from Table 3, the resin in accordance with thepresent invention (i.e resin I-A) has a substantially higher iodinecontent than the commercially available resins or the resin prepared inaccordance with the prior art (i.e. resin I-B).

Example 5.4

Comparative Iodine Content in Water During Stagnation

100.00 gm of each resin was mixed with 125 ml of water in Erlenmeyerflask which was sealed airtight. The water mixture was allowed to stand20 degrees Celsius for 7 days. A water sample was then taken from eachwater mixture and subjected to a standard method for testing water forthe presence of Iodine using the Leuco Crystal Violet IodometricSpectrophotometer Technique so as to obtain the “ppm” concentration ofiodine in the water. The results are shown in Table 4 below.

TABLE 4 Resin bleed iodine concentration (ppm) I-A 1.7 ppm I-D 2.5 ppmNOTE: As may be seen from table 4, the resin of the present invention(resin I-A) has a significantly lower iodine bleed lose into water thanthe commercial product (resin I-D).

EXAMPLE 5.5

Resin Size Study

Two grams of dry resin was examined with a microscope having amicrometer scale system and sized by eye. The results are shown in Table5 below.

TABLE 5 Size (ie. approximate effective Resin diameter size) - lowest tohighest AMBERLITE I 401 S 0.35 mm to 0.52 mm I-A 0.60 mm to 1.20 mm I-B0.40 min to 1.00 mm

EXAMPLE 6

Simultaneous tests were conducted to compare the antimicrobial activityof a iodinated resin in accordance with the present invention (resinI-A, above) and a prior art iodinated resin (resin I-D, above). A seriesof batch solutions was prepared; each batch solution contained adifferent microorganism. A batch solution was divided into test portionsso that the comparative tests could be carried out against each of theresins at the same using a respective test portion of the batchsolution; the volume of the test portions was 150 liters. The sameamount of each of the resins was supported in a respective fixed bedconfiguration (i.e. the resins were disposed in a cylinder 1 cm highhaving an internal diameter of 3 cm). The respective test solutions wereallowed to pass downwardly through each of the resins in the samefashion and at the same flow rate (i.e. the test conditions were thesame for each resin). The tests were carried out at ambient conditionsof temperature and pressure. The microorganisms and test results were asfollows:

-   -   a) A lyophilized strain of Klebsiella terrigena (A.T.C.C. 33257)        was rehydrated in phosphate-buffered saline (PBS) and was        subcultivated in order to obtain a broth with a bacterial        density of 10⁹ cfu/ml (cfu=colony forming units). The broth was        treated to obtain media free monodispersed bacterial cells. The        bacterial solution was then diluted in water to provide the test        batch solution at an initial concentration of 4.8×10⁷ cfu per        100 ml.

Microbiological monitoring of the test water was done throughout theexperiment. Sampling of the filtered water was done at intervalsprescribed by the: U.S.E.P.A. (protocol section 3.5.1 d 1(b)) with themembrane-filter technique for KLEBSIELLA described in: 17th edition ofStandard Methods for the examination of water and wastewater, pp. 9-97to 9-99.

A test solution containing Klebsiella terrigena (A.T.C.C. 33257) at aninitial concentration of 4.8×10⁷ per 100 ml was passed through the fixedbed of each resin at a flow rate of 125 ml/min to 200 ml/min. Thetreated volume of solution for each resin was 150 liters in total.Sampling of the effluent or treated solution was effected at intervalscorresponding with a predetermined percentage of the test portionshaving passed through the resins. The results are shown in Table 6abelow:

TABLE 6a Total % of test Microorganism concentration in test solutionpassed effluent for each resin type (cfu/ml) through the resin Resin I-DResin I-A  0% 0/0/0 0/0/0 25% 0/0/0 0/0/0 50% 0/0/0 0/0/0 60% 0/0/00/0/0 75% 0/0/0 0/0/0 90% 0/0/0 0/0/0 100%  0/0/0 0/0/0

As may be seen from table 6a the destruction of the bacteria was totalin the case of each resin.

-   -   b) Poliovirus 1 (A.T.C.C VR-59) was obtained as a lypholized        pellet, rehydrated in PBS, and grown on buffalo green monkey        (BGM) kidney cells from the Armand Frappier Institute (IAF) in        Laval Quebec. Standard cell culture and virological procedures        were used to obtain a concentration of 3×10⁷ of monodispersed        virion particles per ml.

Enough virus was added to a holding tank to obtain a concentration ofabout 1×10⁷ pfu per liter for the test batch solution(pfu=plaque-forming units).

The assay technique consisted of inoculating healthy BGM cells with asmall amount of filtered water at regular intervals. If a virus particlewere present, a plaque would be observed on the cellular bed thru thegellified maintenance media that contained a vital stain.

A test solution containing Poliovirus 1 (A.T.C.C VR-59) at an initialconcentration of 1×10⁷ pfu per liter was passed through the fixed bed ofeach resin at a flow rate of 125 ml/min to 200 ml/min. The treatedvolume of solution for each resin was 150 liters in total. Sampling ofthe effluent or treated solution was effected at intervals correspondingwith a predetermined percentage of the test portions having passedthrough the resins. The results are shown in Table 6b below:

TABLE 6b Total % of test Virus concentration in test effluent solutionpassed for each resin type (pfu/l) through the resin Resin I-D Resin I-A 0% 0/0/0 0/0/0 25% 0/0/0 0/0/0 50% 0/0/0 0/0/0 60% 0/0/0 0/0/0 75%0/0/0 0/0/0 90% 0/0/0 0/0/0 100%  0/0/0 0/0/0

As may be seen from table 6b the destruction of the Poliovirus was totalin the case of each resin.

-   -   c) Rotavirus (A.T.C.C VR-899) was obtained, rehydrated in PBS,        and grown on A-104 cells obtained from IAF. The method used to        obtain the diluted poliovirus above was used with respect to the        rotavirus. The yield for rotavirus grown on MA-104 cells was        2×10⁶ pfu/ml. After dilution in the holding tank the        concentration of the virus was 1×10⁷ pfu per liter.

The assay techniques were similar to those used for poliovirus, only thecell type and vital stain changed since they are specific for each typeof virus. The same sampling strategy was applied.

A test solution containing Rotavirus (A.T.C.C VR-59) at an initialconcentration of 1×10⁷ per 100 ml was passed through the fixed bed ofeach resin at a flow rate of 125 ml/min to 200 ml/min. The treatedvolume of solution for each resin was 150 liters in total. Sampling ofthe effluent or treated solution was effected at intervals correspondingwith a predetermined percentage of the test portions having passedthrough the resins. The results are shown in Table 6c below:

TABLE 6c Total % of test Virus concentration in test effluent solutionpassed for each resin type (cfu/ml) through the resin Resin I-D ResinI-A  0% 0/0/0 0/0/0 25% 0/0/0 0/0/0 50% 0/0/0 0/0/0 60% 0/0/0 0/0/0 75%0/0/0 0/0/0 90% 0/0/0 0/0/0 100%  0/0/0 0/0/0

As may be seen from table 6c the destruction of the Rotavirus was totalin the case of each resin.

EXAMPLE 7

An iodine bleed test was conducted on the Resin I-A and Resin I-Dmentioned above. The tests were conducted as follows:

A pressure syringe was filled with 20 grams of resin (inner chamber of 3cm×13 cm). Using a peristaltic pump 750 ml/min of R/O water (sterilized)was pumped through the syringe; the resin being maintained in thesyringe by suitable mesh means. The total water passed through the resinwas 5 liters.

The results of the tests are given in the graph shown in FIG. 1; i.e.ppm iodine in effluent vs total volume water passed through resin. Thebleed test results as shown in the graph compares iodine (I₂) and iodide(I⁻) in effluent of treated water after passing through each of theresins.

EXAMPLE 8

The bacteriocidal longevity of the Resin I-A and Resin I-D weredetermined for purposes of comparison. Two fixed resin bed devices wereprovided, one device loaded with one of the resins and the other deviceloaded with the other resin; each device was loaded with 75.00 grams ofa respective resin. The tests for each resin bed were conductedsimultaneously. For each resin bed, the solution to be treated waspassed there through at a flow rate of 2.0 liters per minute, with aninitial concentration of Klebsiella terrigena 1×10⁷ cfu/100 ml. Theeffluent was tested at intervals for the presence of viable bacteria. Asmay be seen in the graph of FIG. 2, the volume of contaminated solutionat which bacteria start to pass through the prior art resin (i.e. ResinI-D) is significantly less than the breakthrough volume for the resin ofthe present invention (i.e. Resin I-A). From FIG. 2 it may be seen thatthe bacteriocidal activity of the iodinated resin of the presentinvention (Resin I-A) is superior to that of the known resin (ResinI-D), i.e. the Resin I-A has about a 16% superior antimicrobial activityin relation to the amount of water treatable by a given amount ofiodinated resin.

EXAMPLE 9

Preparation of Resin I-A′ of the Present Invention

An iodinated resin (Resin I-A′) was prepared following the procedures ofexamples 1 to 4 except that for the resin, Amberlite IR-400 (OH⁻) (wasused and for the procedure of example 3 the elevated temperature andpressure conditions were set at 121° C. and 15 psig respectively. ResinI-A′ was used in the following examples.

EXAMPLE 10

Comparative Iodine Content in Effluent Air

Two cartridges as illustrated in FIGS. 3 and 4 were prepared. Eachcartridge contained 50.0 grams of dry (granular) resin (i.e. and noactivated carbon bed). One cartridge contained Resin I-A′ and the othercontained Resin I-D.

The cartridges were each disposed in a system as illustrated in FIG. 5but which did not contain any atomizer indicated generally by thereference number 7. The system included a housing 8 for defining an airpath and had an air inlet 9. The resin cartridge 1 was disposed at theoutlet of the air path. The air leaving the cartridge 1 was directed byappropriate tubing to a collector station 10. The system included avacuum pump 11 (but not the air sterilizer system 12) for drawing airfrom inlet 9 through the system. In operation a cartridge 1 wasreleasably placed in position (e.g. snap fit, etc.) and the vacuum pumpactivated so as to draw outside air (indicated by the arrow 13) into thehousing 8. The air passed through the cartridge 1 as shown by the arrows14. The air leaving the cartridge 1 was then directed to the collectorstation 10. The air entering the collector station 10 impinged upon aiodine collector solution 15 (comprising double reverse osmosis water,i.e. RIO water) in the collector station 10. Air leaving the collectorstation 10 thereafter passed through the pump 11 and was exhausted tothe outside air.

Using the above described system, each, cartridge was submitted to anair velocity there through of 0.7 Liter/per minute for a period of 50minutes. The collector station 10 included 50 ml purified R/O water (thewater was then subjected to standard optical coloration techniques (i.e.the Leuco violet technique as referred to in example 5.4 above) todetermine the total iodine content).

The Results of the Tests are Shown in Table 10a:

TABLE 10a Resin type total iodine (I₂) Resin I-A′ 0.4 ppm Resin I-D 1.1ppm

The results of the tests as shown in table 9a means that each gram ofboth of the resin types will add a definite amount of iodine to theeffluent air, namely as indicated in table 10b.

TABLE 10b iodine (I₂) release Resin type per gram resin Resin I-A′ 0.014Mg/m³/gr Resin I-D 0.031 Mg/m³/gr

Thus, for example, if a gas mask cartridge as discussed above contained50.0 gm of iodinated resin, the resins would emit the level of iodineset out in table 10c below

TABLE 10c Resin type iodine (I₂) release Resin I-A′ 0.7 Mg/m³ (=50 gr ×0.014 mg/m³/gr) Resin I-D 1.5 Mg/m³ (=50 gr × 0.031 mg/m³/gr)

The “Committee of the American conference of governmental industrialhygienist.” emits the “threshold limit value” or T.L.V. for commonchemicals. The iodine T.L.V. is 1.0 Mg/m³ for air analysis for humanbreathing during a period of 8 hrs. Thus, while the Resin I-D releases50% more iodine than the maximum T.L.V. indicated above, the Resin I-A′(of the present invention) releases iodine at a level well below theT.L.V. The Resin I-A′ could thus be used without an iodine scavenger;this would, for example, simplify the construction of a gas maskcartridge. The known Resin I-D on the other hand could also be used butit would require some sort of iodine scavenger (e.g. activated carbon)to obtain the necessary iodine T.V.L. level.

EXAMPLE 11

The Resin I-A′ was tested with different micro-organisms under differentconditions for the sterilization of air.

EXAMPLE 11.1

Direct Contact Sterilization Study

Resin I-A′ was evaluated for its biocidal capacity on direct contactwith Klebsiella terrigena in relation to a time reference and a humiditycontent variation; namely water content variations of 110%, 50% & 0%(relative to the weight of dry resin) and time variations of 2, 5, 10,and 15 seconds.

After preparing the three resins with their respective humidity content25 glass rods were sterilized. A vial containing 25 ml of the inoculum(Klebsiella terrigena: 10⁹× ml) was also prepared.

The testing proceeded as follows with respect to the dry resin. A glassrod was immersed in the inoculum and then immersed in the dry resin for2 seconds. The glass rod was then washed in 100 ml phosphate buffer towash out the microorganisms. Following the standard method forevaluation of water, the collected sample was then plated and incubated.This procedure was then repeated for 5, 10 and 15 seconds.

The procedure was also repeated for the two other different humiditycontent batches of Resin I-A′. The results of the test are shown intable 11a.

TABLE 11a number of viable microorqanisms per time period % humidity 2sec. 5 sec. 10 sec. 15 sec. 110% 16 0 0 0  50% 23 1 0 0  0% 67 15 0 0

As may be seen from table 11a, the Resin I-A′ whether wet, humid or drydestroys large quantities of resistant bacteria in direct contact, andthis destruction occurs on a relatively rapid time base as demonstratedabove.

EXAMPLE 11.2

Klebsiella terrigena Eradication Study: Air Flow

A study was done to evaluate the biocidal effectiveness of dry ResinI-A′ versus Klebsiella terrigena.

The system used was the system illustrated in FIG. 5. The systemincluded an atomizer 7 (of known construction) disposed in a housing 8provided with an air opening 9. The system had a vacuum pump 11 for thedisplacement of air through the system. The system included an airsterilizer 12 comprising a hollow housing 10 inches high by about 2.5inches in inner diameter and filled with about 1.5 kilograms of ResinI-A′; the sterilizer has an air inlet and outlet. The air path throughthe cartridge 1 is designated by teh arrows 14. The atomizer 7 containedan inoculum 16 (Klebsiella Terrigena: 10^(7×100) ml). For the test, theair flow at arrow 13 was set at 30 liters per minute and the air inflowat arrow 17 for the atomizer was set at 8 liters per minute; theatomizer 7 injected mist or spray 18 of inoculum into the air in the airpath and the inoculated air then passed through cartridge 1 as shown bythe arrows 14.

A cartridge 1 as illustrated in FIGS. 3 and 4 was prepared using dryResin I-A′ (65.0 gm giving a bed depth of 1.15 cm). The cartridge 1 wassubmitted to an injection of a total of 10 ml of inoculum over a timeperiod of 15 minute. Sampling was done at 0 minutes, 7.5 minutes and at15 minutes. The samples were collected in a standard impringer (e.g.collector station 10) as shown in FIG. 5. After, processing 100 ml ofthe water from the impinger on microbiological paper filter andincubation, the results show total eradication of Klebsiella terrigena.

EXAMPLE 11.3

Bacillus pumilus Eradication: Air Contact

A study was carried out using the system shown in FIG. 6. To the extentthat members of the system are the same as those used in the systemillustrated in FIG. 5, the same reference numerals are used to identifythe same parts. The main difference between the system of FIG. 5 andthat of FIG. 6 is that the system of FIG. 6 uses a microbiologicalfilter paper 19 to collect the microorganisms leaving the cartridge 1;the filter paper is maintained in place in any (known) suitable fashion.

An inoculum 20 of the thermophilic bacteria Bacillus pumilus wasprepared and injected at a concentration of 10³/liter of influent air. Acartridge mask containing 65.00 gm of Resin I-A′ was prepared as for theprevious example. The test ran for 30 minutes.

All effluent (velocity at arrow 13 being 30 liters per minute) wascollected on the microbiological filter paper 19 (from millepore), thenlain in a T.S.A. (trypticase Soy Agar) and incubated. The results showedtotal eradication of Bacillus pumilus.

EXAMPLE 11.4

Bacillus subtilis Sterilization in Air Flow

This test was performed with Bacillus subtilis in a mixture of 40%active bacteria/60% spores. The system shown in FIG. 6 was used with thecartridge comprising 50 grams of Resin I-A′ (giving a bed depth of 0.85cm). The controlled concentration of processed air was 55bacteriological units per liter. The air velocity was 23 liter perminute for 80 minutes.

Once the 80 minutes ended, the millepore filter paper was collected,lain on T.S.A. (after neutralisation of potential iodine with sodiumthiosulfate 5%) and incubated for 48 hours at 37 degree Celsius. Theresults show a total eradication of micro-organisms.

EXAMPLE 11.5

Bacillus subtilis: Resin I-A′ Versus Glass Beads in Air Flow

In order to assess the retention factor of micro-organisms on inertmaterials this test was performed. Also, to evaluate the migrationfactor of the biological vector, a sequential incubation was performed.

Two gas cartridges were built in accordance with FIGS. 3 and 4, namely:

a) Resin I-A′ cartridge 10 micron polypropylene upstream mesh (filter);50.00 gm of Resin I-A′ giving a bed depth of .85 cm; 10 Micronpolypropylene downstream mesh (filter). b) Glass bead cartridge 10micron polypropylene upstream mesh (filter); 50.0 gm sterile glass beads(from Fisher Scientific and having the same size as the beads of ResinI- A′) giving a bed depth of .85 cm; and 10 Micron polypropylenedownstream mesh (filter).

The system as shown in FIG. 6 was used for the tests.

Simultaneously, the two cartridges were, once inserted in theirrespective testing chamber, submitted to a velocity of 23 liter perminutes for 40 minutes with a microbiological load of 40 bacteria perliter in the influent.

Once the test period completed, the two cartridges were dissected insterile conditions and the microbiological filter paper recovered. Eachof the materials composing the masks were individually, as well as thefilter paper, were incubated in T.S.A. for 48 hours at 37 degreeCelsius. The results are shown in table 11b.

TABLE 11b Resin I-A′ Glass beads upstream mesh: 2 cfu tnc* cfuResin\beads: 0 cfu tnc* cfu downstream mesh: 0 cfu 220 cfumicrobiological 0 cfu 86 cfu filter paper: *tnc = microorganisms toonumerous to count

As may be seen from table 11b the Resin I-A′ eradicated all bacteria andno living micro-organism can live in the resin bed. The Glass beads onthe other hand have a mechanical filtering capacity in regards to thebiological vector but migration occurs rapidly thus obtaining “tnc”results (too numerous to count) on the upstream mesh and the beadsthemselves. The migration keeps on going through the filter until itreaches the microbiological paper filter in large number. Also, theglass beads filter becomes severely contaminated, causing a disposalproblem.

EXAMPLE 11.6

Bacillus subtilis

Resin bed depth comparison. This test was performed to establish thebiocidal effectiveness of the Resin I-A′ in regards to themicrobiological eradication of Bacillus subtilis. The system of FIG. 6was used.

Two cartridges as illustrated in FIGS. 3 and 4 containing respectively30.00 gm (giving a bed depth of 0.5 cm) and 50.00 Gr (giving a bed depthof 0.85 cm) of Resin I-A were submitted to 60 minutes of air pumping ata velocity of 27 liter per minutes. A total of 23 ml of inoculum at aconcentration of 10⁷ per ml were injected into the system.

A positive control yielded a concentration of 275 cfu/liter of air atthe microbiological sampling site.

The results show total eradication for both cartridges.

EXAMPLE 11.7

Bacillus subtilis: Longevity Study in Air Flow

A cartridge of FIGS. 3 and 4 containing 30.00 gr (bed depth: 0.5 cm) ofResin I-A′ was submitted to an air flow velocity of 25 liter/minutecontaining a concentration of Bacillus subtilis of 112 cpu/liter(positive control for correlation) for a period of 3 hrs.

The test was done using the impinger technique (of FIG. 5), with 300 mlof sterile water. Once the 3 hours completed the water from the impingerwas filtered on a microbiological membrane as referred in standardmethod for analysis of water and waste water 17th edition, pp.9-97 To9-99. The growth media was trypticase soy agar. The results afterincubation for 48 hours at 37.5 degree Celsius was total eradication.

EXAMPLE 12

Studies of the Fixation of Iodine at Different Iodine Concentrations

Resin I-A′, Resin I-B′, Resin I-B″ and Resin I-A″ were prepared asfollows:

Resin I-A′ was prepared as described in example 9.

Resin I-B′ was prepared following the procedures of examples 1 and 2except that for the resin, Amberlite IR-400 (OH⁻) (from Rohm & Hass) wasused.

Resin I-B″ was prepared following the procedures of examples 1 and 2(using Amberlite 401-S) except that the amount of the I₂/KI mixture wasadjusted so as to provide a resin comprising about 30 percent iodine atthe end of the procedure in example 2; the mixture obtained at the endof the procedure of example 2 was divided into two equal parts and onepart was subjected to a wash to provide the iodinated resin obtained asat the end of the procedure in example 2; and

Resin I-A″ was prepared by taking the remaining one half part of theintermediate mixture obtained in the preparation of Resin I-B″(mentioned above) and subjecting the mixture to the procedure of example3 except that the elevated temperature and pressure conditions were setat 121° C. and 15 psig respectively.

The iodine content of the above iodinated resins was determined inaccordance with the procedure outlined in example 5.3. The resins werealso subjected to an iodine bleed test as outlined in example 7. Theresults are shown in table 12 below:

TABLE 12 Resin type Iodine % Iodine leach Resin I-B′ 43.5 0.15 ppm ResinI-A′ 41.8 0.05 ppm Resin I-B″ 30.5  0.3 ppm Resin I-A″ 29.0 0.05 ppm

As may be seen from table 12, subjecting the resin to a hightemperature/pressure treatment results in the iodine being moretenaciously fixed to the resin at different iodine concentrations.

EXAMPLE 13

Air Study with I-B″

The procedure of example 11.6 was followed using 30 grams of Resin I-B″and Bacillus subtilis at a concentration of 275000 cfu per cubic meter.It was found that the Resin I-B″ eradicated only 7 to 10% of themicroorganisms. The results of the test show that the Resin I-B″ is notas effective at eradicating microorganisms from air as is the ResinI-A′; it would be necessary to have substantially more of Resin I-B″ inorder to totally sterilize air as compared with the Resin I-A′.

EXAMPLE 14

Studies of the fixation of iodine at different temperatures as well asat atmospheric and elevated pressures

Resin 1A, Resin 2B, Resin 3A and Resin 4B were prepared as follows:

The starting resin was Amberlite 402 (OH⁻) from Rohm & Hass. 1000 gramsof this resin was pretreated following the procedure outlined in example1(i). The obtained washed resin was divided into four 200 gram portions.An iodine sludge (four portions, one for each of the above mentioned 200gm portions of resin) was prepared as outlined in example 1(ii) butusing twice the amount of materials such as the iodine and the potassiumiodide. The 200 gm resin portions were each iodinated using a respectiveiodine sludge as follows:

Resin 1A was prepared, using an above mentioned 200 gm resin portion anda respective iodine sludge, following the procedures of examples 2 to 4except that for the procedure of example 3 the elevated temperature andpressure conditions were set at 121° C. and 15 psig respectively (whilethe reaction time at the elevated conditions remained at 15 minutes);

Resin 2B was prepared, using an above mentioned 200 gm resin portion anda respective iodine sludge, following the procedure of example 2 exceptthat the temperature of the shaking bath was maintained at 40° C.;

Resin 3A was prepared, using an above mentioned 200 gm resin portion anda respective iodine sludge, following the procedures of examples 2 to 4except that for the procedure of example 3 the elevated temperature andpressure conditions were set at 121° C. and 15 psig respectively whilethe reaction time at these elevated conditions was set at 1.5 hoursrather than at 15 minutes; and

Resin 4B was prepared, using an above mentioned 200 gm resin portion anda respective iodine sludge, following the procedure of example 2 exceptthat the reaction mixture was placed into a container having a loosefitting cover; the container containing the reaction mixture was placedinto a heated water bath; the temperature of the reaction mixture wasbrought up to a boiling temperature of 100° C. to 105° C. over a periodof 20 minutes and was maintained at the boiling temperature of 100° C.to 105° C. for a period of 15 minutes; and thereafter the mixture wasallowed to cool to room temperature over a period of about 1 hour (thereactor was not a pressure sealed reactor but one wherein the loosefitting cover allowed gas/vapour to escape such that the reaction wascarried out (essentially) at atmospheric pressure—extra safetyprecautions had to be taken due to the violent sputtering of thereaction mixture and to the toxicity of the released gas/vapour). Thedensity of each of the obtained iodinated resins was determined inaccordance with the procedure outlined in example 5.1. The iodinecontent of the above iodinated resins was determined in accordance withthe procedure outlined in example 5.3. The resins were also subjected toan iodine bleed test as outlined in example 7. The results are shown intable 14 below:

TABLE 14 Resin type Iodine % Iodine leach Density Resin 1A 46.4 0.5 ppm1.616 gm\ml Resin 2B 48.1 1.5 ppm 1.694 gm\ml Resin 3A 45.0 0.5 ppm1.661 gm\ml Resin 4B 45.7 1.0 ppm 1.595 gm\ml

As may be seen from table 14, subjecting the starting iodine/resinmixture to a treatment at essentially atmospheric pressure and atemperature of 100° C. to 105° C. or lower (resin 2B and 4B) does notresult in the iodine being as tenaciously fixed to the resin as whenusing both a temperature above 100° C. and a pressure above atmosphericpressure (resins 1A and 3A).

EXAMPLE 15

Sterilisation Barrier Combinations for Use as Wound (Sterilisation)Dressings

EXAMPLE 15.1

Preparation of Sterilisation Foam Dressing

The following starting materials were used to prepare a sterilisationfoam dressing:

-   -   a particulate iodinated resin prepared in accordance with        example 9 above; the resin comprising particles or beads of        about 0.3 mm to about 0.7 mm;    -   R/O water; and    -   as foam precursor, HYPOL foamable hydrophilic polyurethane        polymer, (code: #FHP2002) from W. R. Grace & Co., Organic        Chemicals Division, Lexington, Mass. 02173.        The Sterilisation Foam Barrier was Prepared as Follows:    -   150 ml of R/O water was placed into a 300 ml beaker. The water        was heated to 50° C. 10 cc of the HYPOL and 10 gm of the        iodinated resin were simultaneously admixed with the heated        water; mixing was accomplished with a magnetic stirring rod and        was carried out before and after the addition of the HYPOL and        the resin for the purpose of dispersing the resin particles as        homogeneously as possible throughout the mixture. The obtained        foam was set or cured in about 7 minutes; the resin particles        were dispersed throughout the matrix of the foam which was of        porous cellular structure (i.e. sponge like). Once set the        obtained flexible foam had a semi-sphere like form (see for        example FIG. 9); slices of this foam material were taken so as        to provide a foam dressing having an essentially flat face for        being applied against a wound. The obtained sterilisation foam        was flexible and sponge like in that it could absorb liquids        such as water, pus and the like.

EXAMPLE 15.2

Preparation of a Band-Aid Like Sterilisation Dressing

The following starting materials were used to prepare a band-aidsterilisation dressing:

-   -   a particulate iodinated resin prepared in accordance with        example 4 above; the resin comprising particles or beads of        about 0.3 mm to about 0.7 mm; and    -   a strip of polymeric material having an adhesive on one face        thereof (the strip was Compeed).        The Sterilisation Strip Barrier was Prepared as Follows:    -   An open ended ring funnel was disposed over a central area of        the strip on the adhesive face thereof. Resin beads were placed        in the stem of the ring funnel so as to essentially cover the        central portion of the adhesive face defined by the ring; a        plunger was shoved into the ring and a mild pressure was applied        to the resin beads therein. The ring was removed along with        excess resin beads so as to leave behind a single layer of resin        beads fixed to the adhesive face of the strip; the resin beads        in the layer essentially abutted each other. The strip barrier        had a form as shown in FIG. 8; if desired the beads do not have        to abut but could be spaced apart.

EXAMPLE 15.3

Animal Infection Study: Cuts

The foam type sterilisation dressing obtained from example 15.1 wastested as follows:

-   -   Eight male guinea pigs were shaved so as to expose essentially        the same skin area.

The guinea pigs each weighed about 500 to 550 gm and were obtained fromCharles River, Quebec, Canada, a sub-division of Bausch & Lomb; theguinea pigs were quarantined for a period of 48 hours before beingprepared for and subjected to the tests.

The Guinea Pigs were Prepared for the Tests as Follows:

-   -   Essentially the same area of skin of each of the guinea pigs was        anesthetised using Carbocaine-V (chlorhydrate of Mepivacaine USP        2%); this anesthetic has no known sterilisation qualities. An        inoculum comprising a mixture of Staphillococus aureus and        Pseudomonas aeriginosa was prepared at 10⁹ cfu/ml; the ratio of        Staphillococus aureus to Pseudomonas aeriginosa was 1:1. 0.2 ml        of the inoculum was injected under the anesthetised skin of each        animal. A cruciform structured scalpel cut (#) was made above        the inoculum injection area of each of the animals; i.e. the        cuts were 1.0 to 4.0 cm long and 1.0 to 4.0 mm deep. Additional        inoculum was dabbed onto the surface cuts.

The animals were divided into two groups of four animals each, one groupto be used as a control group and the other group as a test group. Afoam sterilisation dressing was applied over the wound for each of theanimals of the test group, i.e. the foam dressing was placed in contactwith the wounded skin area and maintained in place during the period ofthe test. The foam dressings were maintained in place over the woundarea by means of an adhesive strip which was provided with an opening orwindow by means of which a portion of the foam dressing was leftuncovered and exposed to the air. No dressing or sterilisation materialwas applied to the wounds of the animals of the control group.

The four animals of the test group with dressings developed no infectionand the scaring process was initiated after 16 hours. On the other handthe four control animals developed infection and the infection was stillspreading after 72 hours.

The strip type sterilisation dressing obtained from example 15.2 wastested exactly as above for the foam dressing with exactly the sameresults.

EXAMPLE 15.4

Animal Infection Study: Burns

The same studies as described in example 15.3 were carried out exceptthat the lesion was a burn created with a 1.0 cm red hot rod; the hotrod was firmly held against the skin for about 3 to 4 seconds. The sameInoculum as in example 15.3 was injected beneath the burn area and alsodabbed onto the surface of the burned skin. Exactly the same resultswere obtained for the two types of dressings as were obtained for thetests of example 15.3.

EXAMPLE 15.5

Animal Infection Study: Cuts with Continual Contact with InfectiousLiquid

The foam type sterilisation dressing obtained from example 15.1 wastested as follows:

-   -   Four male guinea pigs were shaved so as to expose essentially        the same skin area. The guinea pigs each weighed about 500 to        550 gm and were obtained from Charles River, Quebc, Canada; the        guinea pigs were quarantined for a period of 48 hours before        being prepared for and subjected to the tests.        The Guinea Pigs were Prepared for the Tests as Follows:    -   Essentially the same area of skin of each of the guinea pigs was        anesthetised using Carbocaine-V (chlorhydrate of Mepivacaine USP        2%); the area was also sterilised using 70% isopropyl alcohol. A        cruciform structured scalpel cut (#) was then made in the        sterilised area; i.e. the cuts were 1.0 to 4.0 cm long and 1.0        to 4.0 nm deep.

The animals were divided into two groups of two animals each, one groupto be used as a control group and the other group as a test group. Afoam sterilisation dressing was applied over the wound for each of theanimals of the test group, i.e. the foam dressing was placed in contactwith the wounded skin area and maintained in place during the period ofthe test. The foam dressings were maintained in place over the woundarea by means of an adhesive strip which was provided with an opening orwindow by means of which a portion of the foam dressing was leftuncovered and exposed. No dressing or sterilisation material was appliedto the wounds of the animals of the control group.

An inoculum comprising a mixture of Staphillococus aureus andPseudomonas aeriginosa was prepared at 10⁷ cfu/100 ml; the ratio ofStaphillococus aureus to Pseudomonas aeriginosa was 1:1. Sufficientinoculum was prepared such that each of the animals of the test andcontrol group could be bathed in the inoculum such that the bath liquidwas in continual contact with the wound area, i.e. the bath liquidcovered the dressings. The animals of each group were kept in the bathinoculum for a period of 72 hours.

The two animals of the test group with dressings developed no infectionand the scaring process was in full process. On the other hand the twocontrol animals each had developed infection.

EXAMPLE 15.6

Animal Infection Study: Cuts Contacted with Aerosol Borne InfectiousAgents

The same procedure as for example 15.5 was used except that instead ofbeing maintained in a bath of inoculum, the inoculum was applied usingan atomiser the same as that used for example 11.2 for artificialcreation of airborne infection of a wound; the inoculum used also had10⁹ cfu/ml rather than 10⁷ cfu/100 ml as in example 15.6. 4 ml of theinoculum was sprayed directly on the wound of the control animals and onthe dressing covering the wound of the test animals; the inoculum was soapplied every hour for 8 hours with 72 hours of incubation. The sameresults as in example 15.5 were obtained.

EXAMPLE 15.7

Skin Reaction Study: Iodine Tincture

Three male guinea pigs were shaved so as to expose essentially the sameskin area. The guinea pigs each weighed about 500 to 550 gm and wereobtained from Charles River, Quebec, Canada; the guinea pigs werequarantined for a period of 48 hours before being prepared for andsubjected to the tests.

The Guinea Pigs were Prepared for the Tests as Follows:

-   -   Essentially the same area of skin of each of the guinea pigs was        anesthetised using Carbocaine-V (chlorhydrate of Mepivacaine USP        2%); the area was also sterilised using &O& isopropyl alcohol. A        cruciform structured scalpel cut (#) was made in the sterilised        area; i.e. the cuts were 1.0 to 4.0 cm long and 1.0 to 4.0 mm        deep.

An inoculum comprising a mixture of Staphillococus aureus andPseudomonas aeriginosa was prepared at 10⁹ cfu/ml; the ratio ofStaphillococus aureus to Pseudomonas aeriginosa was 1:1.

The inoculum was only dabbed onto the surface of the wounds of each ofthe animals (no injection of inoculum under the skin). It was found thata 5% iodine tincture locally applied on the wounds would neutraliseinfection provided that the iodine tincture was applied at 0.1 mldirectly after infection and every 2 hours thereafter for 10 hours; theiodine tincture was from Jean Coutu, Quebec, Canada—5% iodine, 3.3% KIand 75% ethanol. However, it was noted that the skin in the periphery ofthe wound was seriously devitalised because of the burning effect of thetincture i.e. of the iodine.

It was also found that the iodine tincture did not stop infection fromoccurring if inoculum was injected under the skin.

EXAMPLE 15.8

Skin Reaction Study: Sterilisation Dressings

Three male guinea pigs were shaved so as to expose essentially the sameskin area. The guinea pigs each weighed about 500 to 550 gm and wereobtained from Charles River, Quebec, Canada; the guinea pigs werequarantined for a period of 48 hours before being subjected to thetests.

A foam sterilisation dressing of example 15.1 was applied over a shaveskin area of each of the animals, i.e. the foam dressing was placed incontact with the shaved skin area and maintained in place during theperiod of the test. The foam dressings were maintained in place over theskin area by means of an adhesive strip which was provided with anopening or window by means of which a portion of the foam dressing wasleft uncovered and exposed to the air. The dressing was maintained inplace for a period of 3 weeks. The covered skin area was examined everytwo days. No redness, rash, inflammation, or any other reaction wasnoted; the covered skin remained healthy.

The above procedure was also carried out using a strip sterilisationdressing of example 15.2. However the dressing was maintained in placeonly for 7 days. Again, no redness, rash, inflammation, or any otherreaction was noted; the covered skin remained healthy.

FIGS. 7 to 11 illustrate a number of example embodiments ofsterilisation barrier combinations of the present invention; some ofthese combinations are also described in example 15 above. FIG. 7 showsa partially cut away perspective view of a sterilisation barrierdressing of tea-bag type construction wherein the iodinated resinparticles or beads (one of which is designated by the reference numeral30) are free flowing but are held together by being enveloped by a fluid(e.g. air-liquid) permeable envelope 31 of (known) pharmaceuticallyacceptable paper or gauze (e.g. a suitable sterile gauze from Johnson &Johnson, Canada). The paper or gauze is permeable to fluids such as airand water but is able to hold onto the particles of iodinated resinenveloped thereby since any holes in the paper gauze are sized to besmaller than the particles of resin. This type of dressing may be maderelatively small or relatively large keeping in mind the size of thelesion that it is intended to cover. The dressing may be made byproviding a sheet of paper or gauze, placing the desired amount of resinparticles thereon and then folding one side edge of the paper or gauzeover the resin particles 30 so as to overlay and abut the opposite side;these abutting side edges 32 and 33 as well as each of the respectiveside edges of the two pairs of adjacent side edges indicated generallyat 34 and 35 may be fixed together in any known manner, for example bycompression, stitching or by the use of any known pharmaceuticallyacceptable adhesive. The fixation of the sides is such that they willtend to maintain their integrity in the face of water, body fluids orbody exudates (e.g. pus). The embodiment shown in FIG. 7 is shown may beconsidered as essentially having a plurality of resin bead layers; itcould of course have only a single such layer.

Alternatively, the sterilisation barrier may take on a band-aid typeaspect as shown in FIG. 8. The combination shown has a flexible carriercomponent 36. A central portion of one side of the carrier component 36has fixed thereto a plurality of beads or particles (one of which isdesignated by the reference numeral 37) of demand disinfectantiodinatedresin. The resin beads 37 are fixed to the surface by a suitableadhesive which is pharmaceutically acceptable and which will maintainthe beads on the carrier component even if exposed to water or bodyfluids or exudates. The portion of the band surface 38 which surroundsthe centrally disposed beads 36 may also be provided with any (known)adhesive which may for example be able to releasably stick thecombination to the skin (e.g. a latex based adhesive). The carriercomponent 36 may, as desired be permeable or impermeable to fluids suchas air, water, pus; preferably, the carrier is permeable to gas such asair, water vapour, etc. at least in the region of the resin beads fixedthereto, i.e. this region is air breathable. The carrier component 36may be of any suitable pharmaceutically acceptable (plastics) material(e.g. the carrier component may be a porous hydrophobic materialpermeable to air and water vapour such as described in U.S. Pat. Nos.3,953,566 and 4,194,041—Gore-Tex). The carrier component complete withan adhesive face may be obtained from Peco Marketing ltd., Montreal,Quebec under the name “Compeed”. FIGS. 9, 10 and 11 show a number offurther embodiments of the sterilisation barrier combination.

FIG. 9 shows a flexible sterilisation foam or sponge type dressing 39for wounds. The dressing comprises a flexible pharmaceuticallyacceptable foam matrix 40 having iodinated resin particles (one of whichis designated with the reference numeral 41) dispersed therein. The foammatrix 40 has a porous open cell structure such that it is permeable tofluids such as air and water and can absorb body liquids in the mannerof a sponge (e.g. the foam is hydrophilic and/or oil loving); the foambarrier is air breathable. The foam matrix 40 as shown has cells ofrelatively small size so as to facilitate the absorption of liquids suchas pus. The resin particles 41 making up the resin disinfectantcomponent are distributed throughout and held or fixed in place by thepolymeric matrix 40 such that surface portions of the resin particlesare exposed within the cells of the matrix 40. The exposed surfaces ofthe resin are available for contact with any microorganisms which mayfind their way into the cells of the body of the barrier combination;contact with the resin devitalises the microorganisms.

The foam sterilisation barrier or dressing 39 as shown in FIG. 9 has asemi-spherical like shape. The flat surface 42 may be applied to a woundor cut. The dressing may be held in place by any suitable means such asfor example any suitable strapping or by adhesive tape means.Preferably, the sterilisation foam dressing 39 is held in place suchthat at least a portion of it is exposed (e.g. exposed to the air); thusthe means for holding the foam in place may be an adhesive strip whichhas a central opening exposing at least a portion of the foam when thefoam is held in place. Once in place on the wound, the flexible foamsterilisation barrier will sterilise the immediate area of the wound,which it covers and also prevent other infectious microorganisms fromcontacting the wound from outside the body. Surprisingly, however, ithas been found that the sterilisation barrier is also effective not onlyagainst microorganisms at the immediate surface of a wound but alsoagainst those deeper within the body in the area of a cut.

FIG. 10 illustrates another type of flexible foam sterilisation barrier43. It differs from the sterilisation barrier shown in FIG. 9 in thatthe size of the cells (one of which is designated with the referencenumeral 44) is significantly larger than those for the foam shown inFIG. 9; this type of foam may be used as a liner material for wearingapparel to provide the apparel with the ability to protect the wearerfrom (skin) contact with viable microorganisms. The resin beads, spheresor particles (one of which is designated with the reference numeral 45)are, as in the case of the resin spheres 41 for the foam barrier 39 ofFIG. 9, dispersed in the foam matrix and are held or fixed in placethereby such that exposed surfaces of the resin are available forcontact with any microorganisms which may find their way into the cellsof the body of the barrier combination; contact with the resindevitalises the microorganisms.

The foam matrix for the sterilisation barriers of FIGS. 9 and 10 may bemade by admixing (known) starting reactants in (known) manner to make(known) foams which are pharmaceutically acceptable. Known polyurethanefoams may for example be used. In order to make the sterilisationbarrier, the disinfectant resin particles may be admixed with anddispersed (e.g. more or less homogeneously) in the starting reactants atthe beginning of the foam producing reaction. The foam barrier may beset in molds or else cut to the desired shape. The foam sterilisationbarrier may take any desired form such as sheets, films, plugs, and thelike; it may, for example, be molded so as to conform to the shape ofportion of the body to which it is to be applied.

As mentioned above a (flexible) pharmaceutically acceptable hydrophilicfoam matrix may be obtained using water and HYPOL foamable hydrophilicpolyurethane polymer starting material from W. R. Grace & Co.Lexintington Mass. U.S.A.

The pore or cell size of the foam barrier may be adjusted in knownmanner; for example by altering the reaction temperature. For example inthe case of HYPOL a temperature of about 50 to 70° C. may be used toobtain small pore sizes and a lower temperature of about 35 to 45° C.may be used to obtainer larger sized pores.

FIG. 11 shows a cross sectional portion of a sandwich type textilematerial 46 which incorporates a flexible large cell size sterilisationfoam layer 47. The sandwich comprises two outer flexible clothe typelayers 48 and 49 which are fixed to the central sterilisation foambarrier 46 in any suitable manner (e.g. by an adhesive, melt fusion,etc.). The two outer layers 48 and 49 may be of any desired material;they may be permeable or impermeable to fluids such as air, watervapour, water and the like. They may for example be of cotton,polypropylene, etc.; or a Gore-tex type material mentioned above. Asheet of textile material as shown may cut into pieces of various shapesneeded to form such protective wearing apparel as may be desired, e.g.coats, pants, socks, face masks (e.g. full face masks or masks coveringonly the mouth and nose) and the like.

The flexible foam layer 47 can be made in any known manner provided thatdisinfectant resin particles are dispersed in the reaction mixtureduring the reaction such that the end product foam also has the resinparticles dispersed in the foam matrix and any microorganism able topenetrate into an interior cell of the foam may be able to contact aresin particle exposed into the cell and be devitalised thereby. Thefoam barrier as in the case of the foam dressings mentioned may beconfigured to be permeable to fluids such as air, water, etc.

The textile material 46 may be formed by first forming a sheet of thesterilisation foam; by providing sheets of the desired outer layers; andthen gluing the elements together such that the foam is sandwichedbetween the two other outer layers.

Alternatively, a mold may be used wherein opposed surfaces of the moldare provided with a respective outer layer; the foam starting materialsare introduced between the layers; and foaming activated such that thefoam layer is produced in situ.

Although shown with two outer layers the combination of FIG. 11 may ofcourse have only one such cloth like layer. Additionally if the outerlayer or layers are permeable to fluids such as air, water, pus and thelike, the wearing apparel made there from could as needed double as akind of sterilisation dressing; the textile may thus for example be airbreathable.

Additionally although the foam sterilisation barrier has been describedin relation to a flexible foam it may be a stiff foam depending upon theapplication; again the stiff foam matrix may be prepared in knownmanner.

An alternate embodiment of the sandwich type textile may be made whereinthe foam matrix is omitted; in this case the beads may be placed betweenthe outer layers and the beads may be fixed in place for example by anadhesive or by melt fusion depending on the nature of the layers (e.g.melt fusion may be considered if the layers are of thermoplasticsmaterial; the textile may of course be so made as to preserve theflexibility of the combination.

EXAMPLE 16

Iodinated weak base anion exchange resins prepared in accordance withthe present invention as described in example 4 were compared withiodinated weak base anion exchange resins prepared in accordance withteachings of prior art (i.e. U.S. Pat. No. 3,923,665) as described inexample 2 after suitable washing to remove elutable iodine. Theseiodinated weak base anion exchange resins were examined with respect tocertain physical characteristics as described in example 5. The resultsare shown in table 15 below.As may be seen from table 15, compared with the iodinated resinsprepared in accordance with teachings of prior art, the iodinated resinsprepared in accordance with the process of the present invention haveabout 15% to 25% higher wet densities and much less iodine leach inwater during stagnation.

TABLE 15 Start Weight Wet Density 24 hr Stagnation Leach Polymer ModelNo. Base (gm) (gm/ml) % Iodine (ppm) 48 hr Stag Leach (ppm) IODINEIMPREGNATION WITHOUT THE PROCESS OF THE PRESENT INVENTION Amberlite IRA67 Weak 125 0.33 48.4 29.6 43.8 Amberlite IRA 402 (OH) Strong 125 0.3748.5 11.0 23.8 Amberlite IRA 402 (Cl) Strong 125 0.38 47.5 8.1 10.7Amberlyst A-21 Weak 125 0.29 46.3 18.7 34.5 COMPARATIVE CHEMICALANALYSIS AFTER THE PROCESS OF THE PRESENT INVENTION Amberlite IRA 67Weak 125 0.38 47.8 17.2 20 Amberlite IRA 402 (OH) Strong 125 0.46 48.03.9 3.7 Amberlite IRA 402 (Cl) Strong 125 0.47 48.5 4.6 2.34 AmberlystA-21 Weak 125 0.37 44.2 5.6 6.35

1. A process for preparing an iodinated resin, said iodinated resinbeing an iodinated anion exchange resin, said iodinated anion exchangeresin is in a form selected from the group consisting of chloride Cl⁻and hydroxyl OH⁻, said process comprising a conversion step, saidconversion step comprising contacting an anion exchange resin with asufficient amount of an iodine-substance absorbable by said anionexchange resin such that said anion exchange resin absorbs saidiodine-substance so as to convert said anion exchange resin to saidiodinated resin, said iodine-substance being selected from the groupconsisting of I₂ and polyiodide ions having a valence of −1, wherein forsaid conversion step at least a portion of the absorption ofiodine-substance is effected at elevated temperature and at elevatedpressure, said elevated temperature being a temperature higher thanabout 100° C. and up to about 210° C., said elevated pressure being apressure greater than atmospheric pressure and up to about 100 psig. 2.A process as defined in claim 1 wherein said elevated pressure is apressure of about 2 psig and up to about 100 psig.
 3. A process asdefined in claim 1 wherein said elevated pressure is a pressure of about5 psig and up to about 100 psig.
 4. A process as defined in claim 1wherein said elevated pressure is a pressure of up to about 100 psig. 5.A process as defined in claim 1 wherein said elevated pressure is apressure of from about 5 to about 35 psig.
 6. A process as defined inclaim 1 wherein said elevated pressure is a pressure of from about 5 toabout 20 psig.
 7. A process as defined in claim 1 wherein said elevatedtemperature is a temperature of about 102° C. and up to about 210° C. 8.A process as defined in claim 1 wherein said elevated temperature is atemperature of about 115° C. and up to about 210° C.
 9. A process asdefined in claim 1 wherein said elevated temperature is a temperature ofup to about 150° C.
 10. A process as defined in claim 1 wherein saidelevated temperature is a temperature of about 115° C. to about 135° C.11. A process as defined in claim 1 wherein said elevated temperature isa temperature of about 102° C. and up to about 210° C. and said elevatedpressure is a pressure of about 5 psig and up to about 100 psig.
 12. Aprocess as defined in claim 1 wherein said elevated temperature is atemperature of about 110° C. and up to about 210° C. and said elevatedpressure is a pressure of about 5 psig and up to about 100 psig.
 13. Aprocess as defined in claim 1 wherein said elevated temperature is atemperature of about 115° C. and up to about 210° C. and said elevatedpressure is a pressure of from about 5 to about 35 psig.
 14. A processas defined in claim 1 wherein said iodine-substance comprises triiodideions of formula I₃ ⁻.
 15. A process as defined in claim 1 wherein saidanion exchange resin is an anion exchange resin having a primary,secondary or tertiary aromatic or aliphatic amino group.
 16. A processas defined in claim 1 wherein said anion exchange resin is contactedwith a composition comprising a mixture of KI, I₂ and a minor amount ofwater, and a mole ratio of KI to I₂ initially being about
 1. 17. Aprocess as defined in claim 15 wherein said anion exchange resin is in ahydroxyl form OH⁻, wherein said anion exchange resin is contacted with acomposition comprising a mixture of KI, I₂ and a minor amount of water,and a mole ratio of KI to I₂ initially being about 1, wherein saidelevated temperature is a temperature of about 102° C. and up to about210° C. and wherein said elevated pressure is a pressure of about 2 psigand up to about 100 psig.
 18. A process for preparing an iodinatedresin, said iodinated resin being an iodinated anion exchange resin,said iodinated anion exchange resin is in a form selected from the growconsisting of chloride Cl⁻ and hydroxyl OH⁻, said process comprising aconversion step, said conversion step comprising contacting an anionexchange resin with a sufficient amount of an iodine-substanceabsorbable by said anion exchange resin such that said anion exchangeresin absorbs said iodine-substance so as to convert said anion exchangeresin to said iodinated resin, said iodine-substance being selected fromthe group consisting of I₂ and polyiodide ions having a valence of −1,wherein said conversion step comprises an initial conversion stagefollowed by a second conversion stage, said initial conversion stagecomprising contacting said anion exchange resin with saidiodine-substance at a temperature of about 100° C. or lower so as toobtain an intermediate composition, said intermediate compositioncomprising residual absorbable iodine-substance and an intermediateiodinated resin, said second conversion stage comprising subjecting saidintermediate composition to elevated temperature and elevated pressure,said elevated temperature being a temperature higher than about 100° C.and up to about 210° C., said elevated pressure being a pressure greaterthan atmospheric pressure and up to about 100 psig.
 19. A process asdefined in claim 18 wherein said elevated pressure is a pressure ofabout 2 psig and up to about 100 psig.
 20. A process as defined in claim18 wherein said elevated pressure is a pressure of about 5 psig and upto about 100 psig.
 21. A process as defined in claim 18 wherein saidelevated pressure is a pressure of up to about 100 psig.
 22. A processas defined in claim 18 wherein said elevated pressure is a pressure offrom about 5 to about 35 psig.
 23. A process as defined in claim 18wherein said elevated pressure is a pressure of from about 5 to about 20psig.
 24. A process as defined in claim 18 wherein said elevatedtemperature is a temperature of about 102° C. and up to about 210° C.25. A process as defined in claim 18 wherein said elevated temperatureis a temperature of about 115° C. and up to about 210° C.
 26. A processas defined in claim 18 wherein said elevated temperature is atemperature of up to about 150° C.
 27. A process as defined in claim 18wherein said elevated temperature is a temperature of about 115° C. toabout 135° C.
 28. A process as defined in claim 18 wherein said elevatedtemperature is a temperature of about 102° C. and up to about 210° C.and said elevated pressure is a pressure of about 5 psig and up to about100 psig.
 29. A process as defined in claim 18 wherein said elevatedtemperature is a temperature of about 110° C. and up to about 21 00C.and said elevated pressure is a pressure of about 5 psig and up to about100 psig.
 30. A process as defined in claim 18 wherein said elevatedtemperature is a temperature of about 115° C. and up to about 210° C.and said elevated pressure is a pressure of from about 5 to about 35psig.
 31. A process as defined in claim 18 wherein said iodine-substancecomprises triiodide ions of formula I₃ ⁻.
 32. A process as defined inclaim 18 wherein said anion exchange resin is an anion exchange resinhaving a primary, secondary or tertiary aromatic or aliphatic aminogroup.
 33. A process as defined in claim 18 wherein said anion exchangeresin is contacted with a composition comprising a mixture of KI, I₂ anda minor amount of water, and a mole ratio of KI to I₂ initially beingabout
 1. 34. A process as defined in claim 18 wherein said anionexchange resin is in a hydroxyl form OH⁻, wherein said anion exchangeresin is contacted with a composition comprising a mixture of KI, I₂ anda minor amount of water, and a mole ratio of KI to I₂ initially beingabout 1, wherein said elevated temperature is a temperature of about102° C. and up to about 210° C. and wherein said elevated pressure is apressure of about 2 psig and up to about 100 psig.
 35. A process asdefined in claim 18 wherein said initial conversion stage comprisescontacting said anion exchange resin with said iodine-substance at apressure of from about 0 to less than about 2 psig.
 36. A process asdefined in claim 18 wherein said initial conversion stage comprisescontacting said anion exchange resin with said iodine-substance at atemperature of from about 20° C. to about 40° C. and at essentiallyambient pressure ranging from a pressure of about 0 psig to less thanabout 1 psig.
 37. A process as defined in claim 18 wherein said initialconversion stage is affected for a time period of about 1 minute ormore.
 38. A process as defined in claim 18 wherein said initialconversion stage is affected for a time period of from about 1 minute toabout 24 hours.
 39. A process for preparing an iodinated resin, saidiodinated resin being an iodinated weak base anion exchange resin, saidiodinated anion exchange resin is in a form selected from the groupconsisting of chloride Cl⁻ and hydroxyl OH⁻, said process comprising aconversion step, said conversion step comprising contacting a weak baseanion exchange resin with a sufficient amount of an iodine-substanceabsorbable by said anion exchange resin such that said anion exchangeresin absorbs said iodine-substance so as to convert said weak baseanion exchange resin to said iodinated weak base anion exchange resin,said iodine-substance being selected from the group consisting of I₂ andpolyiodide ions having a valence of −1, wherein for said conversion stepat least a portion of the absorption of iodine-substance is effected atelevated temperature and at elevated pressure, said elevated temperaturebeing a temperature higher than about 100° C. and up to about 210° C.,said elevated pressure being a pressure greater than atmosphericpressure and up to about 100 psig.
 40. A process as defined in claim 39wherein said elevated pressure is a pressure of about 2 psig and up toabout 100 psig.
 41. A process as defined in claim 39 wherein saidelevated pressure is a pressure of about 5 psig and up to about 100psig.
 42. A process as defined in claim 39 wherein said elevatedpressure is a pressure of up to about 100 psig.
 43. A process as definedin claim 39 wherein said elevated pressure is a pressure of from about 5to about 35 psig.
 44. A process as defined in claim 39 wherein saidelevated pressure is a pressure of from about 5 to about 20 psig.
 45. Aprocess as defined in claim 39 wherein said elevated temperature is atemperature of about 102° C. and up to about 210° C.
 46. A process asdefined in claim 39 wherein said elevated temperature is a temperatureof about 115° C. and up to about 210° C.
 47. A process as defined inclaim 39 wherein said elevated temperature is a temperature of up toabout 150° C.
 48. A process as defined in claim 39 wherein said elevatedtemperature is a temperature of about 115° C. to about 135° C.
 49. Aprocess as defined in claim 39 wherein said elevated temperature is atemperature of about 102° C. and up to about 210° C. and said elevatedpressure is a pressure of about 5 psig and up to about 100 psig.
 50. Aprocess as defined in claim 39 wherein said elevated temperature is atemperature of about 110° C. and up to about 210° C. and said elevatedpressure is a pressure of about 5 psig and up to about 100 psig.
 51. Aprocess as defined in claim 39 wherein said elevated temperature is atemperature of about 115° C. and up to about 210° C. and said elevatedpressure is a pressure of from about 5 to about 35 psig.
 52. A processas defined in claim 39 wherein said iodine-substance comprises triiodideions of formula I₃ ⁻.
 53. A process as defined in claim 39 wherein saidweak base anion exchange resin is an anion exchange resin having aprimary, secondary or tertiary aromatic or aliphatic amino group.
 54. Aprocess as defined in claim 39 wherein said weak base anion exchangeresin is contacted with a composition comprising a mixture of KI, I₂ anda minor amount of water, and a mole ratio of KI to I₂ initially beingabout
 1. 55. A process as defined in claim 39 wherein said weak baseanion exchange resin is in a hydroxyl form OH⁻, wherein said weak baseanion exchange resin is contacted with a composition comprising amixture of KI, I₂ and a minor amount of water, and a mole ratio of KI toI₂ initially being about 1, wherein said elevated temperature is atemperature of about 102° C. and up to about 210° C. and wherein saidelevated pressure is a pressure of about 2 psig and up to about 100psig.
 56. A process for preparing an iodinated resin, said iodinatedresin being an iodinated weak base anion exchange resin, said iodinatedanion exchange resin is in a form selected from the group consisting ofchloride Cl⁻ and hydroxyl OH⁻, said process comprising a conversionstep, said conversion step comprising contacting a weak base anionexchange resin with a sufficient amount of an iodine-substanceabsorbable by said anion exchange resin such that said weak base anionexchange resin absorbs said iodine-substance so as to convert said weakbase anion exchange resin to said iodinated weak base anion exchangeresin, said iodine-substance being selected from the group consisting I₂and polyiodide ions having a valence of −1, wherein said conversion stepcomprises an initial conversion stage followed by a second conversionstage, said initial conversion stage comprising contacting said weakbase anion exchange resin with said iodine-substance at a temperature ofabout 100° C. or lower so as to obtain an intermediate composition, saidintermediate composition comprising residual absorbable iodine-substanceand an intermediate iodinated resin, said second conversion stagecomprising subjecting said intermediate composition to elevatedtemperature and elevated pressure, said elevated temperature being atemperature higher than about 100° C. and up to about 210° C., saidelevated pressure being a pressure greater than atmospheric pressure andup to about 100 psig.
 57. A process as defined in claim 56 wherein saidelevated pressure is a pressure of about 2 psig and up to about 100psig.
 58. A process as defined in claim 56 wherein said elevatedpressure is a pressure of about 5 psig and up to about 100 psig.
 59. Aprocess as defined in claim 56 wherein said elevated pressure is apressure of up to about 100 psig.
 60. A process as defined in claim 56wherein said elevated pressure is a pressure of from about 5 to about 35psig.
 61. A process as defined in claim 56 wherein said elevatedpressure is a pressure of from about 5 to about 20 psig.
 62. A processas defined in claim 56 wherein said elevated temperature is atemperature of about 102° C. and up to about 210° C.
 63. A process asdefined in claim 56 wherein said elevated temperature is a temperatureof about 115° C. and up to about 210° C.
 64. A process as defined inclaim 56 wherein said elevated temperature is a temperature of up toabout 150° C.
 65. A process as defined in claim 56 wherein said elevatedtemperature is a temperature of about 115° C. to about 135° C.
 66. Aprocess as defined in claim 56 wherein said elevated temperature is atemperature of about 102° C. and up to about 210° C. and said elevatedpressure is a pressure of about 5 psig and up to about 100 psig.
 67. Aprocess as defined in claim 56 wherein said elevated temperature is atemperature of about 110° C. and up to about 210° C. and said elevatedpressure is a pressure of about 5 psig and up to about 100 psig.
 68. Aprocess as defined in claim 56 wherein said elevated temperature is atemperature of about 115° C. and up to about 210° C. and said elevatedpressure is a pressure of from about 5 to about 35 psig.
 69. A processas defined in claim 56 wherein said iodine-substance comprises triiodideions of formula I₃ ⁻.
 70. A process as defined in claim 56 wherein saidweak base anion exchange resin is an anion exchange resin having aprimary, secondary or tertiary aromatic or aliphatic amino group.
 71. Aprocess as defined in claim 56 wherein said weak base anion exchangeresin is contacted with a composition comprising a mixture of KI, I₂ anda minor amount of water, and a mole ratio of KI to I₂ initially beingabout
 1. 72. A process as defined in claim 56 wherein said weak baseanion exchange resin is in a hydroxyl form OH⁻, wherein said weak baseanion exchange resin is contacted with a composition comprising amixture of KI, I₂ and a minor amount of water, and a mole ratio of KI toI₂ initially being about 1, wherein said elevated temperature is atemperature of about 102° C. and up to about 210° C. and wherein saidelevated pressure is a pressure of about 2 psig and up to about 100psig.
 73. A process as defined in claim 56 wherein said initialconversion stage comprises contacting said weak base anion exchangeresin with said iodine-substance at a pressure of from about 0 to lessthan about 2 psig.
 74. A process as defined in claim 56 wherein saidinitial conversion stage comprises contacting said weak base anionexchange resin with said iodine-substance at a temperature of from about20° C. to about 40° C. and at essentially ambient pressure ranging froma pressure of about 0 psig to less than about 1 psig.
 75. A process asdefined in claim 56 wherein said initial conversion stage is affectedfor a time period of about 1 minute or more.
 76. A process as defined inclaim 56 wherein said initial conversion stage is affected for a timeperiod of from about 1 minute to about 24 hours.
 77. A process forpreparing an iodinated resin, said iodinated resin being an iodinatedanion exchange resin, said iodinated anion exchange resin is in a formselected from the group consisting of chloride Cl⁻ and hydroxyl OH⁻,said process comprising a conversion step, said conversion stepcomprising contacting an anion exchange resin with a sufficient amountof an iodine-substance absorbable by said anion exchange resin such thatsaid anion exchange resin absorbs said iodine-substance so as to convertsaid anion exchange resin to said iodinated resin, said iodine-substancebeing selected from the group consisting of I₂ and polyiodide ionshaving a valence of −1, wherein for said conversion step at least aportion of the absorption of iodine-substance is effected at elevatedpressure, said elevated pressure being a pressure greater than 2 psigand up to about 100 psig.
 78. A process as defined in claim 77 whereinsaid iodine-substance comprises diatomic iodine I₂.
 79. A process asdefined in claim 77 wherein said iodine-substance comprises triiodideions of formula I₃ ⁻.
 80. A process as defined in claim 77 wherein saidconversion step is carried out in a closed, air-tight container.
 81. Aprocess as defined in claim 80 wherein said elevated pressure is apressure of about 5 psig and up to about 100 psig.
 82. A process asdefined in claim 80 wherein said elevated pressure is a pressure of upto about 100 psig.
 83. A process as defined in claim 80 wherein saidelevated pressure is a pressure of from about 5 to about 35 psig.
 84. Aprocess as defined in claim 80 wherein said elevated pressure is apressure of from about 5 to about 20 psig.
 85. A process as defined inclaim 80 wherein said anion exchange resin is an anion exchange resinhaving a primary, secondary or tertiary aromatic or aliphatic aminogroup.
 86. A process as defined in claim 80 wherein said anion exchangeresin is contacted with a composition comprising a mixture of KI, I₂ anda minor amount of water, and a mole ratio of KI to I₂ initially beingabout
 1. 87. A process as defined in claim 80 wherein said anionexchange resin is in a hydroxyl form OH⁻, wherein said anion exchangeresin is contacted with a composition comprising a mixture of KI, I₂ anda minor amount of water, and a mole ratio of KI to I₂ initially beingabout 1, wherein said elevated pressure is a pressure of about 2 psigand up to about 100 psig.
 88. A process for preparing an iodinatedresin, said iodinated resin being an iodinated anion exchange resin,said iodinated anion exchange resin is in a form selected from the groupconsisting of chloride Cl⁻ and hydroxyl OH⁻, said process comprising aconversion step, said conversion step comprising contacting an anionexchange resin with a sufficient amount of an iodine-substanceabsorbable by said anion exchange resin such that said anion exchangeresin absorbs said iodine-substance so as to convert said anion exchangeresin to said iodinated resin, said iodine-substance being selected fromthe group consisting of I₂ and polyiodide ions having a valence of −1,wherein said conversion step comprises an initial conversion stagefollowed by a second conversion stage, said initial conversion stagecomprising contacting said anion exchange resin with saidiodine-substance at a temperature of about 100° C. or lower so as toobtain an intermediate composition, said intermediate compositioncomprising residual absorbable iodine-substance and an intermediateiodinated resin, said second conversion stage comprising subjecting saidintermediate composition to elevated pressure, said elevated pressurebeing a pressure greater than 2 psig and up to about 100 psig.
 89. Aprocess as defined in claim 88 wherein said iodine-substance comprisesdiatomic iodine I₂.
 90. A process as defined in claim 88 wherein saidiodine-substance comprises triiodide ions of formula I₃ ⁻.
 91. A processas defined in claim 88 wherein said conversion step is carried out in aclosed, air-tight container.
 92. A process as defined in claim 91wherein said elevated pressure is a pressure of about 5 psig and up toabout 100 psig.
 93. A process as defined in claim 91 wherein saidelevated pressure is a pressure of up to about 100 psig.
 94. A processas defined in claim 91 wherein said elevated pressure is a pressure offrom about 5 to about 35 psig.
 95. A process as defined in claim 91wherein said elevated pressure is a pressure of from about 5 to about 20psig.
 96. A process as defined in claim 91 wherein said anion exchangeresin is an anion exchange resin having a primary, secondary or tertiaryaromatic or aliphatic amino group.
 97. A process as defined in claim 91wherein said anion exchange resin is contacted with a compositioncomprising a mixture of KI, I₂ and a minor amount of water, and a moleratio of KI to I₂ initially being about
 1. 98. A process as defined inclaim 91 wherein said anion exchange resin is in a hydroxyl form OH⁻,wherein said anion exchange resin is contacted with a compositioncomprising a mixture of KI, I₂ and a minor amount of water, and a moleratio of KI to I₂ initially being about 1, wherein said elevatedpressure is a pressure of about 2 psig and up to about 100 psig.